UNITED STATES OF AMERICA WASHINGTON, D. C. 8PO 16—67244-1 A BRIEF HISTORY O F EPIDEMIC and PESTILENTIAL DISEASES j WITH THE PRINCIPAL PHENOMENA OF THE PHYSICAL WORLD, WHICH PRECEDE AND AC- COMPANY THEM, OBSERVATIONS DEDUCED FROM THE FACTS STATED. IN TWO VOL UMES. * By NOAH WEBSTER, Author ©f Diflertations on the Englifli Language and feveral other Works—Member of the Connecticut Academy of Arts and Sciences —of the Society for the Promotion of Agriculture, Arts and Man- ufactures, in the State of New-York—of the American Academy of Arts and Sciences, and correfponding Member of the Hiftori- cal Society in MafTachufetts. VOL. II. v " EAR T F 0 R D : PRINTED BY HUDSON tsf GOODWIN. 1799. ^PUBLISHED ACCORDING TO dCT QF CONGRESS-^ CONTENTS of the SECOND VOLUME. SECTION IX. ** ILLS of mortality for the two lajl centuries, with the princi- pal phenomena of the elements, - - Page I SECTION X. Remarks on the H'tflory and Tables, - - - io SECTION XL Peflilential periods exhibited by means of an increafe of mortality in dlflant parts of the world, - - - - 17 SECTION XII. Of the Influenza or epidemic Catarrh, 30 SECTION XIII. Of the order, conneSlon and progrejfton of peflilential epidemics, 37 SECTION XIV. Of the Extent of a peflilential fate of Air, - - 62 SECTION XV. Of the Phenomena which attend peflilential periods, with conjeSures concerning the caujes, - - - - - 78 SECTION XVI. Of Contagion and Infeclion, - - - - 135 SECTION XVII. Of the means of preventing or mitigating peflilential difeafes, 214 SECTION XVIII. Of the difappearance of the plague in fome parts of Europe, and of new difeafes, ------- 256 ADDENDA. Of the Lunar Influence, - - - - - 282 Of Eleclrlcity........305 Of the popular modes of guarding agalnfl Infeclion, - 327 On Venefecllon,.......33° On Vapor or Mephltlc Air, - - - - 332 On the Revolution of certain Comets, - - - 337 Poflfcript, . .....34-© ERRORS. VOL. I. Page 337, line 12, erafe the following words—K but its pragrefs -wai limited to onejireet near the •water." See the fact, in page 345. 340, The laft paragraph, fave one, is mifplaced—it belongs to the poftfeript about the middle of page 347. 310, line 28, for Tome, read Torre. . + VOL. II. Page 3, In the account of deaths in Drefden in 1631, for 144, read 844. This correction is material, as the true num- ber marks the increafed mortality preceding the plague in the two following years; that is, the progrejjion in the peflilential condition of the elements. 52, line 9 from bottom, read Horjiius. 178, line 11, for elyGan read Etcjian. 182, fine 14, for By read But. 191, line at bottom; read repealed. 216, line 3, read axillary. 292, line 4, from bottom for obferved read obfeured. A few literal errors are not noticed; and poflibly fome material ones may have cfcaped obfervation. SECTION IX. Sills of mortality for the two lafl centuries, with the principal phenomena of the elements. \^J UR accounts of difeafes and the phenomena of the world, which appear to be connected with them, are altogether imperfect. But in the two laft centuries, we have a tolerable hiftory of dif- eafes, and occafionally an account- of the feafons, and remarka- ble occurrences. In the following tables, the reader will find the bills of mortality for London, Augfburg, DrefUen, Bofton, one Church in Philadelphia, with a kw bills of Paris and Dub- lin ; to which are prefixed fuch of the remarkable phenomena of the elements, as I have been able to collect. As winter makes a part of two years, the word fevere is fet againft the year which preceded the winter. Thus againft the year 1607, the word fevere refers to the winter of 1607-8. The blanks denote, ei- ther that nothing lingular occurred in thofe years, or that I have no account of the occurrences. Further enquiries might proba- bly enable me to fill many of thofe blanks. Bills of mortality do not exhibit a complete view of epidemics; as fome of the more remarkable, efpecially influenza, deftroy but few lives, and the bills of the years when that difeafe alone prevailed, are remarkably low. It is often the immediate pre- curfor of peftilential difeafes in autumn ; in which cafes, the bills of the year are very high. Vol. II. A SEASONS. Other phenomena. A.D. Summer. Winter. Comets Volcanoes. 1600 ' 1601 very dry cool & dry fevere S. America 1602 cold Eng. 1603 Etna 1604 comet S. America 1605 1606 1607 hot fevere comet Etna 1608 hot 1609 fevere comet Etna 1610 very dry 1611 1612 very dry comet 1613 1614 fevere Etna 161? cool 1616 hot and dry 1617 hot and dry t6t8 4 comets 1619 Iceland 16 20 cold comet 1621 16a* dry. Arner. comet DISEASES. general peftilence plague in Portugal and other places influenza, plague plague London, and general famin plague in Cork plague in Cork, dyfentery plague in Denmatk influenza, lore throat in Spain plague in Conftantinople malignant fevers plagut in Conftantinople, fatal fevers in France fatal fmall-pox epidemic, rneafles in Perfia quartan agues general peftilence amonglndiansin America, angina Naph peflilential fevers in France feveis fmall-poic Buri lis in London. Buri. By com- By the in mon dif. plague. Total. AugT 1775 1570 1567 5773 36269 42042 1488 43*3 896 5*19 1298 5948 444 6392 1361 5796 2124 7920 1371 5670 235* 8022 2595 6758 2262 9020 1476 7554 4240 11784 1469 7486 1803 9289 1941 6716 627 7.^43 1891 7778 64 7852 1625 75<>3 16 7519 I73i 7367 22 7389 1444 7850 3/ 7887 177* 8063 9 8072 1631 8280 6' 8286 I5M 959^ 18 9614 1354 8000 9 8009 148J 9691 21 9712 1667 8112 11 8123,1517 1 94*0 16 9436 1*959 A.D. Summer. Winter. Comets Volcanoes *6*3 • | 1624 l6«5 comet &cela-& (Canaries 1626 hot 1627 I 1628 1629 1630 1631 Vefuvius 1633 Vefuvius **.?•? hot fevere En. comet Etna 1634 hot feve. Am, Etna 16.35 mild Et. &Vef. 1636 Et.&Hec. 1637 hot Eng. fevere 1638 hot & dry 1639 dry Ame. 1640 fevere En. 1641 feve. Am. 1642 164.1 hot &dry Et. &Vef. 1644 1645 hot Eng. 1646 1647 hot Ame. > comet 1648 1 1 __________________DISEASES.___________ malignant fevers, precurfors of the plague the fame, increafed mortality, previous to the plague plague in London, Denmark, Italy and Holland, &c. plague in Lyons, Wirtemberg, &c. plague in France, &c. plague in France, Augfbarg, &c. plague in Amsterdam, &c. plague in Vienna, Cambridge, &c. eryfipelous fevers, diieafes of the throat eruptive fevers, plagus in Drefden plague in Drefden, mortality in America, peftil. fevers plague at Ratifbon, fevers in London precurfors of the plague, Augfburg, Leyden, Mentz, &c. (plague plague, London, Nimeguen, Rome, &c. plague in Holland, Denmark lickly year in America, fmall-pox and fevers malignant fevers ficknefs among Indians, America plague, London plague Lond. influenza Amer. fevers (and Shropfhire malig. fevers in Italy, France ScSpain, plague in Ireland London. (Augf fDrcf. 11095 17 IIII2|l$7J 42 J 12199 II I2«io|l370 411 18848 35417 5426j 139* 481 7400 J34 7534^440 7"40 7713 4 7717 2494 411 7740 3 7743 9o11 469 8771 0 8771 1265 39» 9228 1317 0545 909 480 8288 374 8562 »59 144 9537 8 9535 3485 3129 8392 0 8392'3304'4585 10899 1 I0900 4664 721 10651 0 10651 6243 597 12959 10400 23359 790 594 8681 3082 11763 823 1897 13261 3(>3 13624! 638 531 9548 3M 9862 674 1845 11321 1450 12771 586 935 11767 1375 13142 5«7 5*5 11999 1274 13273 593 601 12216 996 13 212 638 1041 9441 1492 "933 659 489 9608 1871 H479 75« 53* 10415 2365 12780 1488 481 10462 3597 I4059 1388 471 9283 611 9894 1208 696 A.D.I Summer. 1^49 1656 1651 1652 1653 1654 *6ss 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 hot dry Eng. dry Eng. dry Eng. hot hot wet Ame dry Ame. wet hot & dry hot cold Eng, winter. fevere fevere mild fevere fevere (eve re cold Comets comet comet comet comet comets comet comet Volcanoes Etna Vefuvius Vef&Ice Etna Etna Etna Etna Etna Etn. great Etna ] Etna Etna Etna Etta DISEASE?. plague in Spain, fmall-pox in Bofton plague in Cork, influenza Europe quiniy.in Italy feveis fickly New-England plague Denmark, Chefter, Turkey, &c. influenza America, general plague Europe plague Italy, &c. plague Genoa influenza Europe, mortality America cynanche trachealis America meafles England meafles, tertians fickly in America fevers Venice, among cattle England, plague Holland purple fever Pruflia, corn mildewed plague London, and over Europe dyfentery over Europe, fmall-pox Bofton fevers Perfia, &c. fever New-York, Europe fmall-pox dyfentery, fevers, meafles, cat plague Weftphalia meafles London, fmall-pox meafles and fmall-pox catarrhs numerous fevers, meafles London, and fmall-pox London.' ' '•' *fAugf 10499 67 10566 940 8749 15 8764 5.13 10444 23 10467 577 12588 16 12604 616 10081 6 10087 575 13*3! 16 13247 764 11368 9 "377 570 13915 6 139*1 641 12430 4 12434 731 14979 14 14993 73i 14720 36 14756 831 15104 M 15118 657 19791 20 19811 668 16542 12 16554 788 15347 9 U356 836 18291 6 18297 761 28710 68596 97306 745 10840 1998 12838 737 15877 769 17294 711 19436 743 20198 734 15 7*9 733 18230 768 17504 75i 2I»0I 842 Drcf. A. B.l Summer. vet&coolE cold Eng. dry and hot 1675 1676 1677 1678 1679 1680 hot and dry 1681 very dry 1682J J683 hot & dry E hot&dryE dry Italy rainy Eu. 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 J 69 7 1698 I699 1700 autum. rainy rainy hot and dry hot hot rainy Euro. cold, wet E. hotAmerica Winter. I Comets levere fevere fevere very feve cold fevere fevere cold Eu. fevere fevere mild, ■♦•■ meteor meteor comet comet comet comet Volcanoes. DISEASES. 'London Etna Etna Etna Etna Etna comet Et.& Vefu comet comet Etna Vefuvius ' comet 'Et. & Vefu, Etna Etna&Icel. Vef.&Band, comet comet S. America influenza Europe meafles and fmall-pox Genoa, England fmall-pox Charlefton, MafT. dyfentery Denmark dreadful plague Morocco, fmall-pox Bofton and S. America catarrhs, plague, Vienna plague Drefden, coughs epidemic, dyfentery murrain among cattle, fpotted fever Dublin, plague at Halle fevers malignant' dyfentery over Europe influenza Europe fpotted fevers Germany, fmall-pox Bofton corn mildewed fpotted fevers Europe, corn blafted, difeafes among cattle malignant fevers influenza Europe malignant fevers apoplexies, meafles, chin cough, fickly America dyfentery among children, fpotted fevers fpotted fever Europe,, catarrh America began influenza America, fpotted fever Europe influenza Europe, plague Philadelphia and Charlefton and Levant fore throat and catarrhs Europe, meafles Augf DrR 17244 9^1 947 18732 913 1284 19067 934 887 20678 943 ioao 21730 945 975 21053 976 6414 239 z"1 860 753 20691 734 1023 20587 808 1290 23202 858 "54 23222 848 937 22609 981 1199 21460I 855 927 22921 860 roil 235021 806 1163 21461J1071 1200 22691I 785 1166 20874! 935 999 2095911084 1071 24100 1106 1426 19047 1048 t227 18638] 927 IO55 2097c 777 IO7O 2018.; 879 919 20795 940 "J9 19443 786 II9 8 A- D,l Summer. .1 i IL ' i i -.— hot & dry hot.& di y dry Euro. hot.dryE very hot 1701 J 702 X703 1704 1705 1706 1707 1708 170 91 1710 1711 171a wet Eng. 1713 wet Eng. 1714 dry & hot 1715 dry 1716 very dry 1717 X7i8jhot, wet 1719 1730 dry Euro. 1721 172a cold, wet 1723 1724 wet Eng. i725j\vetEng. 1726! Winter. very feve, cold Eur. mild fevere fevtre cold Am. cold Comets Volcanoes. Vefuvius comet Etna Vef. & Ten comet comet Ve.newifla meteor DISEASES. comet Vefuvius corset comet meteor comet Vefuvius Iceland a in Iceland plague in the eaft plague Poland, yellow fever N. York, fmall-pox Bofton plague Poland plague in Poland and Hungary, fpotted fevers plague in Ruflia coughs, dyfentery among children meafles England, plague at Waifaw catarrh began in Europe, plague in Thorn catarrh, plague in Dantzick, apoplexies plague in Lithuania, catarrhous fevers Eng. and Holland plague in Copenhagen, an.i among cattle terrible catarrh Europe, plague in the eaft meafles America, plague in Auftria finall-pox and meafles England catarrhous fevers Europe malignant fevers, plague Turkey plague Levant, peflilential fevers, malig. pleurify Amer. plague in Levant and Marfeilies, malig. pkunly Amer. fmall-pox Bofton meafles England fmall-pox in England, plague Barbadoes whooping cough England plague in Egypt LondonJAugf Dref. 240711 906J 992 19481 900 946 20720,1245 1078 22684 1313 964 22097 748 1346 19847 842 1098 21600 805 1523 21291 908 1119 21800 805 1340 24620 811 1214 19833 855 1222 21198 894 H40 21057 860 I383 26569 948 1250 22232 1024 1353. 24436 9°5 1274 23446' 9881908 26523 T 8 1412 28347 997 25454 934 1733 26142 1850 25750 1519 29107 1654 25952 Dub- 1761 25523 in. ,1642 29647 2763 Eoft. 44J *59 220 28a 261 263 291 377 295 363 316 480 413 336 355 45i 380 304 329 1102 273 413 407 324 343 Epif- copal Ch. Philr ;:del- [>hia. "~5 3766 1767 1768 1769 3770 1771 I772 -*773 1774 1775 1776 1777I Summer. hot ve. dry A ve. dry A hot Euro. hot Euro. (hot and (dry Eur. hot hot wet Eng. wet A. E. hot Ame. hot Winter. levere mild Amer. levere Euro. (everc Syria fevere fevere fevere Euro very fevere cold cold Europe A.gr. lhow fevere Euro. fevere Euro. Comet: comet meteor comets comet meteor comet comet comet :omet meteor meteor Volcanoes. DISEASE^. Vefuvius Etna Iceland Vefu. great Vefuvius Azores Etna Etna [Etna, Vefu (and Heckla Veluv. great Ter. & Vef. Vefuvius Pac. inGua. Vefu vitas Ferro malignant fever in Rouen from vapor, anginas America gangrenous fore throat England, Ireland and America catarrhs Europe, anginas Europe and Am. plague Conftanti. influenza America began influenza America, meafles influenza Eu. plague began in Egypt and Smyr. meafles Am. meafles and dyfentery America, plague Levant plague extends in Levant, terrible fever in America influenza America, plague extends Levant, fever America influenza Europe, peftilence Phila. crifis of plague Levant peftile. at Nantucket and in Bengal, diieales among animals yellow fever Cadiz, peftilence in Naples, fmall-pox Bofton dyfenteries Londonl Dub. Bolt dyfentery America influenza Europe difeafes among horfes America (mong cattle fore throat Bofton and other places, meafles Am. difeafes a- fore throat America and Weft-Indies, plague Conftantinople plague in Ruflia, difeafes among catile, catanhs Am. pefti- catarrh America and meafles (lence Bengal meafles, affections of the throat, dyfentery Am. plague Baf- fcartet fever Edin. in fome places in Am. (fora & Bagdadt catarrh in Europe, dyfentery in America and anginas dyfentery America and anginas dyfentery in America and meafles 19276! 22696! 21917 20872] 21313 17576 19604 19830 21063 26326 26143 23202 23230 23911 22612 23639 21847 22434 21770 26053 21656 20884 20541 19048 23334 1825 1897 2002 *55o 1825 1558 1752 1993 2292 2490 2605, 481 434 484 526 434 524 629 576 456 531 407 23071 548 2275I 560 Paris 19664 19875 20808 18427 18719 18941 20374 18518 18400 445 468 417 645 483 482 517 595 596 Phif. 105 94 99 213 97 129 271 174 144 200 180 139 186 133 121 12^ 188 127 r39 157 179 161 156 180 52a AD 778 779 780 781 782 783 Summer. hot hot Eng. dry Ame. hot 784 hot 78; dry Euro. 786 coo! 787 cool 788 789 79oj 791 ve.hot A 792' very fevere cold cold rainyAm. cold (coolfpri. (fevere Eur. (hot fura. (mildAmer. :old 792 793 !aot,dryA mild Amer. levere Euro 794 795 796 797 America hot, rainy autumn ver.dryA cool Am cold Amer. ...... fevere Ame. 79J very hot long and fe- 799ve.dryA(vereA.&E.i Comets halo (me'rs many comet (comet meteoi halo comet cosiet comet Volcanoes. Vefu. great Etna Heckla gre Vefuvius Vefuvius Et. & Vefu Vefuvius great, of Ve Andes and Guadeloupe Teneriffe DISEASES. typhus fevers, plague Conftantinople health bilious fever Philadelphia, general health, plague in Smyrna influenza America influenza Europe, fcarlatina began in Edinburg meafles and fcarlatina Amer. famin India, plague in Egypt, Sec. plague in the eaft, angina America, canine madnefs angina, fevers America yellow fever Cadiz, angina America and England plague Birbary coaft m-afles began N. York and Phila. codfifh ficklv, influenza Eu. { famin in Afia, dearth in A perica, meafL-s America and influ- C enza, death of haddock Europe, plague in the eaft. influenza America (and Grenada plague began in Egypt, bilious peftilence began in New-York plague in Egypt, f arlet fever began in America fcarlet fever Am. and Eng. peftilence Phi1, dyfentery Maryland fcarlatina, peftilence New-Haven and Baltimore, dyfentery (fcarlatina, peftilence Nevv-York and Norfolk, dyfentery C vNew-Hiven, influenza England C fcarlatina, peftilence N. York, Bafton, Charlefton, Newbu- C r'yport, meafles America C influenza Europe, peftilence Phil. Balti. Prov. Norfolk, and C among cats and other animals in Tii' key, canine madneis peft. Phil. N. York, Boft. N. Lond. Portf. Wilming. in Turkey peftflcne? Philadelphia, New-York, Hartford London Paris 20399 20420 20517 20709 17918 19029 17828 18919 20454 r9347 19697 22744 18038 18760 20213 21749 19241 2II79 19288 17014 I7H2 Salem MafT. 175 189 140 114 138 110 144 129 203 148 148] 148 122 195 216 M7 : 3 SECTION X- Remarks on the preceding Hiflory and Tables, I MPERFECT as ancient hiftory is, in regard to the accounts of difeafes, and the extraordinary phenomena of nature, we find that between the year B. C. 480 and the Chi iftian era, a num- ber of violent plagues occurred, moft of which coincided in time with the following phenomena, comets, eruptions of vol* canoes, earthquakes, drouth, fevere winters, difeafes among cattle. Of thirteen comets mentioned in the foregoing hiftory, which are all whofe dates I am able to afcertain, eight of them coincide with volcanic eruptions of Etna, the only" volcano of any note, which the hiftory of that period has recorded ; and eleven of them coincide in time with peftilence. If we con- fider the fcarcity of our materials for a hiftory of thefc phenomena, at that period, and make due allowances for the uncertainty of chronology, we fhall find reafon to be furprifed at fuch a number of thefe coincidences. In feveral inftances we find extreme drouth and very fevere winters to coriefpond in time with comets and eruptions of Etna, conformable to fadls in modern days. On this fubject, hiftoiy is barren alfo for many centuries after the Chriftian era. Yet in every period, even in the dark ages, we find numerous coincidences of the great phenomena above mentioned. All the great plagues that have afflicled mankind, have been accompanied with violent agitations of the elements.* * Modern philofophy objedts to the popular fenfe in which the word, elements, is ufed j fmce it appears that what has ufually been confidered as an element, is found by modern chymiftry to be a com- pound fubftance, rtlolvable into parts, in their nature and properties diftiaA. NotwithfUndiug thefe difcovcrics, I cannot confent to difcaxd the popular ufc of the word iu-.^i. Nature prefents to the fenfes of man, fare, earth, air and wter, in a particular and predominant form II This obfervation refts particularly on the events that preceded and attended the peftilences of the following periods. A. D., 80—167—252—375—400—445—542— 558—590—639- 679—682—745—762—802—905—994—1005—1031— 1044—1069—1106—-1135—1142—1162—1181—1222--: 1242—1300—1347—1368—1400—1477—150c—1531— 1577—1602—1625—1636—1665—1699—1709—1719—- 1728-—1743—1751—1760—1770—1783—1789. Many facts in other periods concur to prove the truth of the remark. - The phenomenon moft generally and clofely connected with peftilence is an earthquake. From all the facts that I can find in hiflory, I queftion whether an inftance of a confiderable plague in any country, can be mentioned, which has not beea immediately preceded or accompanied with convulfions of the earth. If any exceptions have occurred, they have efcaped my refearches. It does not happen that every place where peftilence prevails, is fhaken ; but during the progrefs of the difeafes which I denominate peflilence, and which run, in certain periods, over large portions of the globe, feme parts of the earth, and efpe« cially thofe which abound moft with fubterranean fire, are vio- lently agitated. By adverting to the foregoing hiftory, the reader will find that all thofe years, in which confiderable earthquakes have oc- curred in America, have been remarkably fickly. Thefe years are 1638, 1647, 1658, 1662 and 3, 1668, 1727, 1755, 1783. See the hiftory and the bills of mortality. Even the flighter fhocks, have been attended with confiderable ficknefs, or have introduced a feries of epidemics, being cotemporary with the meafles, influenza or fore throat; as in 1669, 1720, 1737, 1757, 1761, 1769, 1771, 1791, 1797. To enumerate the inftances in Europe and Aria, would be a ufelefs repetition of the events related in the preceding hiftory, to which the reader is referred. Another phenomenon, which, next to earthquakes, appears This is the form in which they appear to be moft ufeful to man, and to be the conftituent materials of other fubftances, as well as the agent* in carrying on the great) vifihle operations of the fyftem. I therefore couGder the popular diftribution a» natural and convenient. 12 {o be moft clofely connected with epidemic d'fcafes, is the erup- tion of fire from volcanic mountains. In this article, hiftory is deficient, or I have not been fortunate enough to find the \vorks peceflary to furnifh a complete view of thefe phenomena. There are whole centuries in which the books I have confulted, men- tion no eruption of Etna and Vefuvius. The account of erup- tions in Iceland, from the year rooo, taken from Pennant's Arctic Zoology, vol. i. 331, is probably complete, cr nearly fo. Of the volcanoes in the Andes, we have very few accounts ; as well as of thofe in the Moluccas. Of thofe in the Arctic regions of Alia and America, we know very little. Notwithftanding thefe defects, we are able, by the eruption? in Italy, Sicily and Iceland, to arrive to fome very important conclufions. The reader rhuft have noticed, in the preceding Hftory, the coincidences in time between volcanic difcharge?, and winters of unufual feverity. Thefe difcharges either precede or follow the winter. Thus the eruptions of 1766, 1779 and J 783, were immediately followed by intenfely cold winters. The fevere winters of 1762-3 and 1779-80, were fpeedily fol- lowed by eruptions. Thefe inftances will ferve as famples of the ordinary courfe of thefe events. Sometimes the eruptions continue or are repeated, for a numfSer of years in fucceflion ; but the eruptions when continued are moderate and the feafons variable. When the volcanoes have been* for fome years, quiet, and that fufpenfion is followed by a great difcharge, it appears to me that fevere winters invariably follow or precede the dif- charge, within a few months. So alfo when an eruption is con- tinued for a number of years, if at any time the difcharge be- comes violent, a fevere winter attends it; as in 1669. Etna was in a ftate of eruption from 1664 to 1679 5 uut in '669, the difcharge was immenfely augmented, and the winters next preceding and following, were very fevere. There are fome years in which eruptions are noted, cf which I find no account, reflecting the feafons. Perhaps fome of thefe will, on further invtftigation, be found to be exceptions. It is to be obferved that, in fome cafes, a fevere winter ex-i tends to both hemifpheres, fometi'mes to one cfnly, and in a few «3 cafes, to a part of a hemifphere only. -Thus in 1C07-S—1683.4. ___i^Sz 3—1766-7—177980—1783-4, the feverity extended to both hemifpheres. In 1640-41—1739-40, and in other in- -fiances, the fevere winter in Europe preceded, by one year, a fimilar winter in America. In a ftw inftances, fevere froft takes place in one hemifphere, during a feries of mild winters in the other ; but this is lefs common. In general, the feverity hap- pens, in both hemifpheres at once, or in two winters in imme- diate fucceflion ; and as far as evidence has yet appeared, this fe- verity is clofely attendant on volcanic difcharges, with very few exceptions. Another phenomenon which ufually coincides in time with fe- vere winters, is the approach of comets. I have been ftruck with furprife at the coincidences of this kind. There are a few inftances on record of mild winters, during the appearance of thefe bodies ; but in thefe cafes, the comets have appeared to be fmall, or to pafs the fyftem at an immenfe diflance from the earth. The large comets and thofe which approach near to the earth, feem to produce almoft uniformly great heat, exceflive drouth, followed by very cold winters, tremendous ftorms of wind, rain, fnew and hail, unufual tides or fwell of the ocean, and ufuallv, volcanic eruptions. How far thefe phenomena are connected, as caufe and effect, future obfervations may de- texmin. Some of them occur fo uniformly in the fame year, that I cannot refiftthe evidence of their connection. After a volcano has been many years quiet, its difcharges are, I believe, always preceded by extreme drouth ; end this defect of water is not only obfervable in the vicinity of the volcano, but often extends over a whole continent, if not over the world. Many inftances have been related ; it is fufficient here to men- tion the exceflive drouth in 1762 and 1782, preceding eruptions of Etna and Heckla. In thefe years, almoft all fprings were exhaufted over a great portion of America. Cold winters fometimes follow wet feafons, but more gene- rally a very hot fummer or very dry autumn. Sometimes two or three fevere winters occur in fucceflion, as in 1766, 67 and 68 .—and in America from 1796 to J799. i4 The years when comets approach, or volcanoes difcharge fire, and when the atmofphere exhibits fiery appearances, as meteors, fleams of light, and mock funs, are, beyond comparifon, the moft tempeftuous. Witnefs the years 1766, 1771 and 72, 17891 1783, 4 and 5, 1788, 1797. In fuch years, the rifle on vef- fels at fea, is gready increafed. As dry feafons ufually precede volcanic eruptions, Co very wet feafons often follow them. This feems not to be the inva- riable courfe of events ; but there are remarkable inftances of deluging rains after thefe difcharges. Witnefs the feafons follow* ing the univerfal convulfions of the earth in 1692 and 3, and 1766. Thus, the electricity is re-conducted to the earth. In every cafe, I believe this remark will be found true ; that the approach of comets, and volcanic eruptions difturb the regu- lar courfe of the feafons. The heat of fummer and the cold of winter are in extremes ; more fnow is generated in winter, and, more hail in fummer ; tempefts are more violent and frequent j meteors more numerous, and rain more unequally diftributed over the earth. A feries of epidemic difeafes, meafles, influenza, affections of the throat, followed by peftilential fevers, appear generally to commence and take their departure, from fome of the great agi- tations of the elements above recited. This at leaft has been the cafe in America in the four laft periods, beginning with 1756-7, 1769 and 70, 1782 and 3, 1788 and 9. This fact will want no authority but a bare inflection of the preceding! hiftory, and tables. The continuance and the varieties of the difeafes feem to de- pend on fimilar difturbances in the elements; and as the dif- charges and motions of the electrical fluid depend on no certain laws that are known, they are irregular, and may contribute to vary the order, and the nature of difeafes. In fome cafes, there has been a continued feries of epidemics, for twenty years, in which the common order is not exatfly obferved ; but this is not frequent. A remarkable inftance occurred between 1727 and I744. Thofe periods in general have been moft diftinguifhed for *5 ficknefs over the world, in which the fire of the earth has exhib- ited the moft numerous and violent effects. Witnefs the period from 1631 to 1637, when the three moft noted volcanoes dis- charged immenfe quantities of fire and lava; and fevere pefti- lence extended over all Europe and America. A fimilar re- mark may be made concerning the period of the laft univerfal peftilence in Europe from 1663 to 1666—alfo from 1691 to 1695—fr°m J727 to 30—1759 to 1764—176910 1772— 1774 to 1777—1783 to 1786—and concerning fome fhorter periods, all of which produced epidemics in both hemifpheres. Slighter eruptions and earthquakes, which are almoft annual, feem to have lefs effect. The fire of the globe is in perpetuat motion or action, and to this great agent, philofophers are agreed, are to be afcribed the changes of feafons, and the generation of rain, hail and fnow. Its operations however are not all of them vifible, nor even perceptible, until they appear by their effefts. It is probable that the invifible operations of the electrical fluid produce more effects than thofe which are feen. Indeed, we may queftion whether moft of the vifible phenomena of that principle, are not mere effects of that action which influences the vegetable and animal world. It is probable to me that neither feafons, earthquakes, nor volcanic eruptions, are the caufes of the principal derangements we behold in animal and vegetable life, but are themfelves the effebls of thofe motions and invifible operations which affect mankind. Hence catarrh and other epi- detnics often appear, before the vifible phenomena of eruptions and earthquakes. P. S. After this work was prepared for the prefs, I was fa- vored by Dr. Mitchill, with fome extracts from a paper of Mr. Holm, a Swede, on the fubject of a volcanic eruption in Ice- land, in 1783, by which it appears that the atmofphere is ren- dered peftilential by difcharges of fire and lava from the earth. This effect is fuppofed to be wrought by a combination of the feptous and oxygenous parts, and may confirm and improve Dr. Mitchill's theory of peftilential air. i6 This eruption I underftand to have been a burfting of fire from the earth, in a place diftant from Heckla. In the neighbor- hood of the column of flame were generated fnow, hail and ex- treme cold. The water that fell in rain was acid and corrofive ; deftroying cattle and men—covering the bodies of cattle with puftles and ulcers, and excoriating the hands and faces of men when it fell on them. It alfo killed vegetables. The effects were felt not only in Iceland, but in Norway, and other parts of Europe. Had this treatife fallen into my hands fome months ago, I might have been able to illuftrate particular parts of my theory by authentic facts, taken from that work. As it is, I muft content myfelf with obferving, that Mr. Holm's obfervations verify my ideas, reflecting the agency of electricity in producing peftilence, and extremes in the feafons. On this theory not only peftilence, but fevere cold, and extreme heat, hail and fnow are all familiar- ly explained, and their connection with volcanic eruptions, and other electrical operations, vifible and invifible, demonftrated. l7 SECTION XI. Peflilential periods exhibited by means of an increafe of mortality in dtflant parts of the world. A: .S there are certain periods when particular epidemics pre- vail over the world or over a hemifphere, and when all other difeafes aifume peculiar malignancy, I have here fubjoined a nurrir ber of bills of mortality, for different and diftant places, to fhow the effect of the general principle of difeafe in remote countries or towns.—Some of thefe periods appear in the foregoing tables, as that between 1623 and 1627; and between 1631 and 1637.—■ A fimihr period occurred between 1718 and 1721. Burials in Amfterdam. Vienna. Breflaw* 7078 745r 8644 9726 7820 7632 The plague raged in Turkey and Syria in 1718-19 and 2Q, alfo at Marfeilles in 1720, in which years or one of them, the bills of mortality were fwelled, even in the north of Europe. I regret that fome of the bills are deficient. The period from 1725 to 1732 is equally remarkable. Burials in A. D. London. 1716 24,436 17 23,446 18 26,523 19 28,347 20 25»454 21 26,142 5205 1458 6110 1255 6825 1816 6490 1482 A. D. London. Amfterdam. Dublin. 1725 25>5-3 26 29,647 9»275 2763 27 28,418 »3»775 2946 28 ' 27,810 11,164 29 29,722 9,618 3206 3P 26,761 3184 Vol IT, c i8 Plague in Egypt and the Levant during this period. From 1739 to 1743. Burials in A. D. London. Amfterdam. Dublin. Bofton. Church in Phila 1739 25>432 7566 2201 554 97 40 30,811 10,066 704 98 41 32,169 9864 279O 555 162 42 27.483 2320 5*7 123 43 25,200 2193 620 116 Plague in Levant, Italy and America. From the year 1744 to 1757 there were many fickly years, but no one diftindt period when an increafe of mortality is obfery., able in all parts of the world, at the fame time. From 1758 to 1764. Burials in A.D. London. Amfterdam. Dublin. Bolton. Church in Phila 1758 I7»5?6 1558 524 129 59 19,604 1752 629 271 60 19,830 7700 1993 576 174 61 21,063 7720 2292 456 144 6* 26,326 8412 2490 531 200 63 26,143 9876* 2605 407 180 64 23,202 8585 2307 548 138 65 23,230 7725 2275 560 18$ Plague in Egypt and the Levant from 1758 101763. Yel- low Fever in Philadelphia in 1762. From 1770 to 1773. Burials in A.D. London. Paris. Amfterdam. Bofton. Ch urch in Phila 1770 22,434 18,719 483 127 71 21,77° 18,941 7983 482 '39 72 26,053 20,374 10,609 517 *57 73 21,656 18,518+ 595 179 74 20,884 596 161 Plague raging in the eaft. * This bill is ftated in the Annual Regifter at 10,506. t In Anderfon's Hiftory of Commerce, Continued, vol. 5. 228 the number of dsaths in Paris in 1773 is ftated to have been 28 518. ' *9 The feries of epidemics, in this period, meafles, influenza and fore throat, were followed by dyfentery in America from 1775 to 1777 inclufive, the mortality of which will appear from the following bills. Burials in A. D. A Church Phi. Hartford. Litchfield. Trinity Church Bofton. Total 1774 l6l 31 27 24 243 15 156 74 31 48 3°9 76 180 79 82 30 371 77 222 72 120 48 462 78 ^3 58 32 63 33<5 79 I42 49 34 35 2,60 It is probable the mortality in the northern ftates of America was every where in that proportion. The fame difeafe made fimilar ravages between 1749 and 1753—in 1759—1765 and 6 —in fome places in 1769.—It was remarkably mortal in 1773. This latter year was in America unhealthy. In Salem, MaiT. the bill of 1773, was raifed to 208, (double the ufisal amount) by the dyfentery. The bill for St. Peterfburgh in Ruflia, was fwel- ied in 1773, one fifth, and in 1777, one fourth. The laft epidemic period, fave one, was from 1781 to-1787 inclufive. The difeafes were influenza, meafles and fcarlatina. Thefe were in general lightar than ufual. In the interior of New- York 'ftate, Vermont, Maflachufetts and New-Hampfhire, the fcarlatina was more fevere and mortal ; but on the fea board and efpecially in Connecticut, it was milder, and many places wholly efcaped it. Yet every where the bills of mortality were fwelled in 1783, 4, 5 or 6, when the plague was raging in the Levant and Egypt. Thisperiod was clofed by remarkably cool fummers, and no dyfentery or peftilential fever of any confiderable violence or extent, fucceeded. Burials in Epifco. Trin. Hart-Weth- Church Chur. ford ers- Litch-Guil-North-To- A.D. Philad. Bofto. Con. field, field, ford. Haven, tal. 1779 H2 35 49 25 34 17 " 3°3 health. 80 155 44 36 17 24 25 10 311 health. 20 ij&t 179 41 37 20 35 17 15 344 influenza; 82 198 39 34 31 34 18 9 363 do. Europe; 83 232 ^6 42 46 42 19 8 445 rmeafles 84 230 61 33 31 34 22 15 426 1& angina. 85 166 41 44 24 30 18 6 329 angina. 86 156 49 50 37 36 19 9 356 angina. 87 H7 32 37 T9 34 24 8 301 health. The fcarlatina and meafles produced their principal effects, it Will be obferved, in Philadelphia and Bofton. The plague raged in Egypt principally in 1783 and 4, and the fcarlatina appeared ih Britain, but without very confiderable mortality. In 1787 the plague prevailed in Egypt and on the Barbary coaft ; and difeafes of the throat were prevalent in England and fome parts bf America. Laft epidemic period from 1789 to 1797 inclufive. Burials in ' Epifco. Prefby. Ger Lu. . . Phila- Ch. N. Ch.N. Ch. N. A.D. ddphia. York. York. York. Total. 1789 1027 337 109 59 1532 meafles and influenza. 90 888 310 107 52 1357 influenza. 91 1290 257 84 60 1691 fever began New-York. 92 1497 404 121 66 2088 fear.began, plague Egy. 93 53°4 4^7 ioi 76 5948 fcarla. pefti. hot & dry. 94 IJ35 4X3 71 71 1690 fome fevers,tempe.fum. 95 2274 554 137 71 3040 peftilence, hot& humid. 96 1602 540 186 62 2390 peftilence New-York. 97 1689 399 130 51 2269 pefti. Phil, cool fummer. The refults above are not perfectly accurate, for the bills in . Philadelphia, it is underftood, are from Auguft to Auguft ; thofe in New-York commence with the year. The bill of the Prefbyterian Church in New-York, for 1797, is by eftimate j the others are taken from regifters. "View of this epidemic period in Connecticut: «« 21 - «« di 8 "3 "^ T3 ^^Er^'i^o ?* S :i « tr 2 „ °^« j« W 5 «cm-„^w„w„ ^ to ^ g^VOOVOcoOo^o^^OO S o * £ 5 q O O •<*■ r- oo JS ji 2 io vo ■62 u ^ .• * # * jjr « o o K VJ to to to to l- S3 O i- 0 % fc £• a o Ofl B C ■ -1 •TJOO^Ol-rOoVOOi-l 4^ " 7, i^covoi^ir^^oooo© ctn O* "d Tj-0^0r)-i0t-t^--' O K qo ee « M ■t to -t f On O <-> 0 «4- CO CO o (LI o NO to o 0 a) 00 to CO *!■ * *o t .S 'C -v Os ■<*- to ON VN £4 <-n M rJ »o to IH N •fi «J O u '3s 0 o ON lr^ co J3 s 3 S t^ 00 V*> NO to 0) C "O -a O 0) 1 o dS to On 00 to ON o On A a» <} O 00 t-~ tO -O "1 S W 1 # 3 u ■3 o • ^J £ # ON ON On ON ON h-l CD # u View of the fame period in Bofton and the neighborhood : Dr. La- Late Stone Char- throp's Dr.El-Dr.Bel- Tri. Chap- les- A.D. Church, liot's. knap's. Ch. el. Salem, town. Total. 1789 52 37 io 50 10 129 22 310 influenza. 90 51 40 8 46 14 203 35 397 do.&meas. 91 34 37 8 31 16 148 26 300 health 11 *792 43 46 16 60 32 148 32 377 do. ex. frri. 91 24 30 11 44 22 148 32 312 do. [pox. 94 45 43 12 33 22 122 26 303 do. 95 34 37 12 45 28 195 38 389 fcarlatina. 96 37 34 16 5° 28 216 • ^5 446 fcarla. fev. 97 37 25 10 47 22 H7 49 337 health. Let it be noted that the effect of the fcarlatina was here in 1795 and '96. The progrefs of the difeafe is diftinctly marked to be from New-York eaftward, from 1793 to 1796. The fcarlatina in 1785 and 6, was moft fevere in Maflachufetts—that in 1794, in Connecticut. The bills in Bofton for 1792 were fwelled by the fmall-pox by inoculation, which is not to be taken into this account of epidemics. The year felected was rather unfavorable, as the condition of the atmofphere was inflammatory, and incli- ned to produce eruptive complaints. The fcarlatina was then making its appearance in the middle ftates. The fpringof 1793* when inoculation was begun at Hartford, was ftill more unfa- vorable ; and the fmall-pox was fo unmanageable as to furprife the faculty. The principles unfolded in this treatife will folve the difficulty. By a bill of mortality for Madeira, it appears that the peftilen- tial principle of the years from 1760 to 64, extended to that healthy iflaffd. A. D. BURIALS. »759> - 1156. 60, - 1356. 61, - 1746. 62, - 1366. 63, - 1118. 64, - 1325. 65* " 1267. 66, - 1037- The following bills for feveral religious focieties in Con- necticut, will exhibit a general view of epidemics from the year 1750. Burials in Guilford Hartford Litchfield Middletown New-Hav A.D. 1 fociety. a focietiei. 1 feciety. 1 fociety. 1 feciety. 1750 19 i — —- — 51 65 64 — — — 52 r 28 J ^_ — — — 53 25 29 — — — 54 *5 20 21 — — SS 22 33 16 — — 56 46 32 28 — — 57 . J7 . 3o 12 — — 58 *7 36 *5 — — 59 20 48 28 — — 60 29 36 24 — — 61 18 42 16 — — 62 18 34 22 - »*4 — 63 18 34 16 22 *3 64 28 42 25 25 19 *5 »5- 24 22 35 *7 dyfentery anfl angina for 3 or 4 years. anginas. anginas in fome places. dyfentery in many places. catarrh. meafles. meafles, dyfentery and fevers. influenza. plague Philadelphia. dyfentery. A.TJ. 1766 67 Guilford I fociety. 12 20 Hartfcrd a focieties. 46 34 Litchfield 1 fociety. 17 22 Middletowi 1 fociety. 29 26 68 21 17 31 30 »9 43 27 *9 27 70 J4 34 18 41 7i 72 10 J7 32 33 35 36 38 38 73 35 32 36 39 74 *3 31 27 30 75 29 74 3* 63 76 32 79 82 78 77 78 29 21 72 58 120 32 42 37 79 80 17 25 49 36 34 24 r9 35 81 17 37 35 37 4^ ^ 18 34 34 45 New-Haven Wethersfield 1 fociety. 1 fociety. Cornwall. 2d — — dyfentery in fome places. 15 — — 21 — — 31 — — angina and dyfentery,meafles. *5 — — angina, meafles. 18 — — catarrh, angina. l9 — — influenza and meafles. 42 — — meafles, angina, dyfentery. 21 — — 21 31 14 59 59 40 10 20 21 ") angina and dyfentery f very fatal. *5 27 3 21 25 *3 12 17 6 15 20 16 influenza. 21 3l 8 influenza in Europe. I* < Guilford Hartford Litchfield Middlctown New-Haven Wethersfield t-H a.;d. 1 fociety. % focieties. 1 fociety. i fociety. 1 fociety. 1 fociety. Cornwal 1. ►™i 1783 l9 42 42 70 12 46 *7 meafles, angina began, bu 84 22 33 34 4* 12 31 8 fcarcely perceived by th 85 18 44 30 40 17 24 5 burials in Connecticut. 86 19 50 36 28 23 37 4 87 24 37 34 26 20 *9 20 88 23 45 27 24 41 22 4 ;o 89 20 48 33 43 H 35 6 meafles, influenza. 90 20 38 54 34 26 36 to meafles, influenza. 91 92 21 *5 41 4^ 4i 23 30 24 12 II 20 37 6 8 > fome fevers, but no epidemc. 93 29 65 80 35 12 40 10 angina, fevers. 94 54 109 56 28 50 47 *9 angina, fevers. 95 55 88 35 16 38 34 9 fevers. 96 19 75 40 35 8 42 15 meafles in many places, 97 25 59 40 25 H 18 8 health in general. l6 From the bills of mortality and preceding hiftory may be de- duced fome interefting obfervations. I. We obferve an order and progreflion in the epidemics, which is in a degree uniform. Periods of peftilence, with fome exceptions, feem to be introduced by meafles and influenza ; then follow difeafes of the throat, or anginas ; laftly peftilential fevers. During the whole period, the meafles, influenza and angina, occa- fionally appear in fpring, autumn and winter ; and rarely, if ever, does a peftilential fever, as plague and yellow fever, occur in a particular city or country, without influenza, angina, meafles or inflammatory fevers in the fpring preceding, for immediate pre- curfors. This is true in the tropical climates, in cafes of epidem- ics ; and fo uniform has been the fact in the temperate latitudes, that I am nearly prepared to fay, that if none of thofe precurfors appear in winter and fpring, no peftilential fever will be epidemic in the following fummer and autumn, unlefs the dyfentery may be excepted. It holds true in every cafe of great peftilence. 2. The progreflivenefs in the peftilential principle is obvious in the augmented bills of mortality, which immediately precede the plague. This arifes from the number and violence of the ma- lignant difeafes which always precede an epidemic peftilence. This augmentation is vifible fome times two years before the plague appears, and almoft always in the fpring months preceding. See the London bills in the years preceding the plague in 1625 —1636—1665. The fame is obfervable in other bills, both in Europe and America. In a few inftances, the bill of the prece- ding year is low ; but in this cafe, fome other epidemic has ufually gone before, and finifhed its courfe ; or the plague is preceded by influenza only, which does not fwell the bill of mortality. 3. Sometimes a feries of epidemics falls with more violence on one hemifphere than on the other ; but perhaps in no inftance has a courfe of difeafes fpread over one continent, v/ithout fhow- ing themfelves on the other. I have not been able to find an in- ftance in which the plague has made great ravages in the eaft, ex- cept when the American continent has been more or lefs affiled by the epidemics above mentioned ; and in fome inftances it is proved that the violence of the fore-throat, influenza, meafles or iL yellow fever, in America, has correfponded with the violence of peftilence in Egypt and the Levant. The commencement of each period of epidemics is nearly cotemporary, in both hemif. pheres.* Thus the great plague in Conftantinople was cotemporary with the fatal angina and dyfentery in America in 1751—alfo in 1755. Cotemporary with the meafles in America in 1758 and 9, was the commencement of the extenfive Levant plague of 1760. Pef- tilence in Perfia was cotemporary with the epidemics of 1773— In 1783 commenced plague in the eaft and epidemics in America —the fame in 1792 and 3. Difeafes of the throat in almoft every inftance prevail at the fame time in Europe and America. 4. In two periods within half a century, a fevere angina and dyfentery have been epidemic together and once for a feries of years, as in 1751, and from 1773 to 1777. This is an excep- tion to the ufual order, and other deviations fometimes occur. 5. As catarrh precedes, fo it follows every fevere epidemic peftilence, and the perfons who have been affected with a pefti- lential fever in fummer, are moft apt to be affected by catarrh at the commencement of cold weather. 6. After fevere peftilential fevers in fummer, the inflammatory fevers of winter, wear the livery of the fummer fevers. They generally carry with them bilious difcharges, and a yellow fkin. They have alfo this remarkable character, that they fpeedily run through the inflammatory diathefis, and become typhus. They are the peftilence of winter ; and fometimes appear before the pet tilence of fummer. This fact alone decides the queftion, that peftilential fevers of fummer are generated on the fpot where they exift ; and derive their malignant and infectious quality fole- ly from the ftate of the elements. This fpecies of inflammatory fever has occurred in many cafes during the winter months, fince the year 1790. In fome cafes it has extinguifhed three, four and five members of a family j as * It fometimes happens that peftilence occurs in Conftantinople, Smyrna or Cairo, when it is not epidemic beyond thofe cities ; owing to peculiar feafons and local caufes. But it never fpreads to Syria, the iflands of the Archipelago, and other neighboring countries, except when epidemic difeafes fpread over the werld. At leaft I have not found an inftance. 28 in Hartford and New-Haven. But it is a moft confoling reflec- tion, that it is lefs frequent than formerly in this country. It has not been epidemic in the northern ftates fince 1761, as far as I can learn. Formerly it was as frightful a calamity as the yellow fever is in this age. In the foregoing hiftory, many examples have been mentioned—as at Fairfield in 1698—-at Waterbury in 1713—at Hartford and Duck Creek in 1720—at Farmington in 1729—at Bethlem, Hartford, Eaft-Haven and New-Haven in 1761—at Hollifton in 1753, &c. Whether the difappear- ance of this difeafe is owing to the clearing of the country, by which the quantity of debilitating miafmata of fummer has been diminifhed, or whether it is the confequence of other alterations in our climate, is not eafily determined. The difappearance of the Long Fever, fo called, is another moft confoling circumftance. This fpecies of typhus fever was formerly one of the moft terrible difeafes of our climate. At prefent it is a rare occurrence. On the whole, we have very clear proof that the quantity of difeafe in this country, has been diminifhed, within half a century. The yellow fever, that is, the peftilential fever of fummer and autumn, was formerly as frequent and as malignant as in this age ; while the inflammatory fevers of winter, and the long fever, have almoft difappeared as epidemics. The intermittents and remit- tents of autumn, are greatly decreafed in the northern ftates ; and the dyfentery has not increafed in frequency or virulence. Anginas have never been fo fatal as they were between 1735 and 1743. It is probable that fome of thefe changes in the character of difeafes may be afcribed to alterations in our climate, or modes of Jiving—and therefore may be permanent. In fome cafes, im- provements in medical fcience and the practice of phyfic may have difarmed difeafes of their terrors. But it is poflible that fome of the changes mentioned are only revolutions in difeafe, occafioned by temporary caufes, and that the fame diforders may, in future periods, recur, with the whole train of formidable fymp, toms. 29 Note.—It has been obferved that the long fever, fo called, has nearly difappeared from our climate. On further enquiry, it appears that this obfervation muft be reftricted to the maritime ftates. The bilious remitting fever that prevailed in Vermont and New-Hampfhire in 1798, and which has re-appeared in tht3 fummer (1799) is of that fpecies. See Medical Repofitory, vol. 3. 5. In the interior of our country, this is a new difeafe j while on the fea-coaft it has become extinct. Shall we conclude from thefe fads, that the difeafe follows or fprings from a par- ticular ftate of cultivation ? In the interior, where the difeafe is now prevalent, the clearing and cultivation of the country were •begun about 30 years ago. On the fea-coaft, where the difeafe has difappeared, the couHtry has been fettled 150 years, and is • generally under cultivation. 3o SECTION XII. Of the Influenza, or Epidemic Catarrh. _/\S the catarrh appears to be the difeafe which is moft clofe- ly connected with peftilence, and the leaft dependent on local caufes or the fenfible qualities of the air, I have collected all the well-defined inftances of this epidemic which have occurred to my refearches, and arranged them in chronological order ; pla- cing againft the year the moft remarkable phyfical occurrences, and mentioning thofe which fell within the years next preceding and following : A. D. CATARRH EPIDEMIC IN 1174, the year before an eruption of Etna, and followed by great mortality. fChafm in the accounts of this difeafe.] 1510, the fame year with an eruption in Iceland, and following great earthquakes. Humid air—a comet appeared the next year. [Chafm.] 1551, the year after an eruption of Etna, and a comet. Seafon wet. 1557, the year afters eruption of Etna. Seafonmoftly wet; but in fome countries dry ; a comet the fame year. [Chaf.] 1580, the year after an eruption of Etna. Cool dry north wind —A comet. 1587, the fame year with an eruption in Iceland—and after *■ comet. 1591, after earthquakes in 1590, and a comet. 1597, the year after earthquakes and a hard winter j rainy fea- fon, and a comet the fame year. 1602, the year after earthquakes, yolcano and fevere winter. Cold and wet feafon. 1610 the year after an eruptiou of Etna, a comet and fevere winter. Seafon very hot and dry. [Chafm.] 1647, Firft catarrh mentioned in American annals. The fame year with violent earthquakes in South-America. A comet. 1650, In Europe the fame year, with an eruption of Etna and earthquakes. 1655, in America, fame year with violent earthquakes in South- America, and eruption of Vefuvius. 1658, in Europe, after a fevere winter ; fummer cool. 1675, in Europe, while Etna was in a ftate of explofion ; mild winter. 1679, 80, in Europe, during or juft after the eruption of Etna; wetfeafon and a comet. 1688, in TLuroft, fame year with an eruption of Vefuvius, after a fevere winter and earthquakes ; this began in a hot fum- mer. 1693, in Europe, fame year with an eruption in Iceland, and great earthquakes ; cool feafon. ' i6§7, 8, in America, after a great earthquake in Peru ; a co- met the fame year, and fevere winter. 16gg, in Europe, in fpring ; great earthquakes the fame year, and a comet. 1708, 9, in Europe, in a fevere winter, after a comet and volcano. 1712, in Europe, the fame year with an eruption of Vefuvius and a comet ; wet feafon. 1717, in Europe, the year of a comet, eruption of Vefuvius, and a fevere winter. 1729, 30, in Europe, the fame year with an eruption in Iceland and Vefuvius ; dry fummer ; a comet. 1733, univerfal, after a comet, a fevere winter and great earth- quakes. 1737, in Europe and America ; an eruption of Vefuvius, great earthquakes and a comet. 1743, m Europe, violent earthquakes. 1744, a comet ; earthquakes. JL 1747, in America and Europe, with a comet and eruption of Etna. 1755, in Europe, with violent earthquakes and eruptions of vol- canoes, and fevere winter. f1757, in America, foon after a comet, and followed by an j earthquake. [1758, in Europe, followed by earthquakes the next year. f 1761, in America ; an earthquake during its prevalence. i 1762, in Europe, before an eruption of Etna ; a comet the (^ fame year. 1767, in Europe ; an eruption of Vefuvius the fame year, and of Etna and Heckla in the preceding year, with a comet and earthquakes. 1772, in America, after an eruption of Vefuvius and Heckla, and a fevere winter. 1775, in Europe, preceded by earthquakes, fmall eruption of Lipari the fame year, and in New-Spain. 1781, in America, the year after an eruption of Etna, and a moft rigorous winter. 1782, in Europe and Afia, the year before the great eruptioh of Heckla. 1788, in Europe, foon after eruptions of Vefuvius and Etna, and earthquakes. 1789, in America, with an eruption of Vefuvius, ]\itt:after a great earthquake at Iceland and in Europe ; warm fummer ; mild winter followed. 1790, in America, after a mild winter. 1795, in England, after an eruption of Vefuvius and a fevere winter. 1797, in Europe, after earthquakes ; a comet the fame year. The accounts of the feafons are moftly from Englifh writers, and refer to England, with fome exceptions. In regard to heat and cold, the feafons are generally uniform in moft countries, on the fame continent; but not in regard to drouth and moifture. Of thefe forty-four inftances of influenza, it may be obferved, from the preceding hiftory, 33 1 i. That moft of them happened, after or during fevere cold, or during moift weather, and in fpring, winter or autumn. Some however, occurred in dry hot feafons, and others in mild winters. 2. Nineteen inftances occurred in years when there was a vol- canic eruption in Italy or Iceland, and eleven others, though in different years, were within a few months of eruptions ; making 30 out of the 44. Two or three others happened near the time of volcanic difcharges in South-America. 3. Almoft all happened in years of earthquakes, or within a few months preceding or following them. 4. Thirty inftances occurred within the year, or a few months preceding or following the appearance of comets. It is further to be obferved that fome of thefe epidemics have been limited to the American hemifphere, at the diftance of three, four or five years from an epidemic of the fame kind in Europe. Such as thofe of 1647—1655—which coincide in time with violent earthquakes in South-America. In other inftances this difeafe fpread over the whole globe ; ufually beginning in America : That is, in the inftances of which I can obtain any correct information. Thus in four inftances, viz. in 1698, 1757, 1761 and 1781, it fpread over the Ameri- can hemifphere one year prior to its pervading the other hemif- phere. And the univerfal catarrh of 1733, which encircled the globe, commenced in America two months before it appeared in Europe. The epidemic of 1782 invaded Europe from the fide of Afia, the year after it appeared in America. In 1788, the influenza in Europe preceded the fame difeafe in America. I regret my want of materials to complete a view of this fubi ject. No regular regifter has been kept in America, of the fea- fons, difeafes and phenomena, from the firft fettlement, and wher ther any notices of all the catarrhs in this country, are in exit tence, I do not know. I have found no account of any, between 1655 and 1698^—nor between the latter year and 1733. One of thefe inftances, that in 1698, came to my knowledge by acci-r dent, as I have mentioned under that year, in the foregoing, hit tory. From the uniform appearance of this epidemic as often as Vwl. H. E 34 once in ten or twelve years, in other periods, we have ground to believe, it has always occurred in nearly the fame periods. This epidemic is evidently the effect of fome infenfible qualities of the atmofphere ; as it fpreads with aftonifhing rapidity over land and fea, uncontrolled hy heat or cold, drouth or moifture. From thefe circumftances and its near coincidence in time with the violent action of fire in earthquakes and volcanoes, there is reafon to conclude the difeafe to be the effect of fome accefs of ftimalant powers to the atmofphere by means of the electrical principle. No other principle in creation, which has yet come under the cognizance of the human mind, feems adequate to the fame effects. I do not confider earthquakes and volcanic erup- tions as the caufes of this epidemic, but as effects of the common caufe and evidences of its exiftence. The courfes of this epidemic are very various. That in 1510 proceeded from Africa to Sicily, Italy and the north of Europe. This difeafe could not be the effect of the eruption in Iceland ; for it appeared firft in fouthern latitudes. If there was a volcanic difcharge about that time in Africa, we might be inclined to afc cribe the diieafe to that caufe ; but it is more probable that it is to be afcribed to an infenfible action of atmofpheric fire,* which - is more general and violent, about the time of eruptions ; and which fire is probably agitated in all parts of the globe, altheugh it produces vifible effects in explofions, in fome particular places only. I think no man can queftion the fact, after reading the preceding hiftory. The courfe of the epidemic in 1551, I am not able to afcer- tain ; nor that in 1557. This invaded Spain in Auguft. The fevere catarrh of 1580 began in the fouth of Europe, in the heat of fummer, and proceeded to the north. The feafon ■ in general was temperate. From that year to 1708—9, I find no account of the courfe of the epidemic catarrh ; but that in 1708—9, began in the north of Europe and proceeded to the fouth. The epidemic of 1729—30, proceeded from Poland and Si- * I ufe this word to exprefs the principle manffefted in elettrical operations, although this is ufually fuppofed to be a cold fufion. Of the nature of this principle, we know little. We fee only its effects. 3* Iefia, to the weft and fouth, and ended about the time of an explo* fion from Vefuvius. The univerfal influenza of 1733, began in America in the au- tumn of 1732. It appeared in Europe in December. That of 1788 appeared in April, May, June and Auguft, in different places. The epidemic in America in 1789, began in the middle ftates, and fpread fouthward and eaft ward. In 1790, it began in about the fame longitude, but in the interior country, and fpread eaft- ward and fouthward. The influenza of 1782 in Europe, came from Afia. Poflibly- it might have travelled from America, acrofs the Pacific to Chi- na and Kamfchatka ; as it was epidemic in America in 1781. This is all I am able to difcover of the origin and direction of this Angular epidemic. It is greatly to be defired, that we might learn precifely the dates of its appearance, the place, the direction of its progrefs, in all cafes, and compare thefe circumftances with "the extraordinary agitations of the elements, which occur about the fame lime. But for this purpofe my materials are incomplete. It is obfervable, however) that the influenza is clofely allied to the meafles. Sometimes the fymptoms are combined in the fame attack, and rarely does one difeafe become epidemic, except juft before or after the other. This proves their alliance : indeed I confider them as different modifications of the fame epidemic. Catarrh is alfo clofely connected with peftilential fevers, and fometimes this is true of the meafles. It is rare indeed that epi- demic plague and yellow fever do not begin and end in catarrhal affections—that is, catarrh precedes in Iprrng, and follows in au- tumn. Sometimes peftilence is preceded and followed by mea- fles and angina. Every epidemic conftitution feems to commence with meafles or influeuza. To thefe fucceed angina, in fome of its various forms, which are all the offspring of the fame parent. Then fol- low peftilential fevers, in the form of dyfentery, yellow fever and plague. Whenever the epidemic conftitution is manifefted by meafles, influenza and affections of the throat, common difeafes, tven in places apparently healthy, become more malignant, arid fporadic cafes of peftilential fever occur in almoft every fituation; Thefe facts are curious, and without attending to them, the philofophy of epidemics cannot be underftood. P. S. After writing the foregoing hiftory, I was able to afcer - tain further particulars of a fevere influenza in America in 1737- Warren, on the yellow fever, mentions this catarrh in Barbadoes in the winter preceding the bilious plague in that ifland in 1738. I have now learnt from two elderly gentlemen, who were then arrived to adult years, that in November 1737, this epidemic in- vaded all parts of the country, fo fuddenly and feverely that neighbors could not vifit each other, and that there were fcarce- ly people in health to perform the ordinary domeftic labors necef- fary to fupport life. If my informants are correct as to the time, this epidemic inva- ded Europe and America in the fame month—the only inftance that I have found ; and an exception to the foregoing remarks. It will be obferved alfo that this inftance coincides with an erup- tion of Vefuvius, and the moft tremendous tempeft in the Eaft- Indies ever known. Let it be noted alfo, that this catarrh was the immediate precurfor of the moft fatal peftilential fever in the Weft-Indies, and one that nearly depopulated Mexico. The catarrh' commenced with or a little before a moft fevere winter. It is remajkable that the extent and violence of this diftem- per mark exactly the feverity of the peftilential fevers which pre- cede and follow it. The two epidemic catarrhs of 1733 an^ 37, invaded the whole globe in the fame year. They were very fevere, and fo were the anginas and plagues of this period ; far beyond what has occurred at any other time, dwing this centu* ry, until the laft period. 37 SECTION XIII. Of the order, connection and progreffion of peflilential epidemics i X N the early periods of the world, little notice appears to have been taken of a connection between epidemic difeafes ; nor have modern writers fupplied this defect in the hiftory of medicin< Hippocrates and Sydenham feem to have been aware of fuch a connection, and the latter author has laid a broad and firm foun- dation for a complete fyftem of truth, on the fubject of epidem- ics. His obfervations were confined to the city of London. Had he extended his view to all parts of Europe, and general- ized his obfervations, he would have found a multitude of fads to juftify his theory, and probably would have railed it above the reach of that obloquy and ridicule, which fucceeding profeflbrs of phyfic, of lefs genius and learning, have eaft on his occult qualities of air. Indeed, it is furprifing that medical men have not purfued the ideas fuggefted by. thefe great fathers of their fcience. Hippo- crates led the way, unlocking the great doctrin of a conftitution or ftate of the atmofphere, calculated to produce particular epi- demic difeafes j a doctrin which Sydenham has purfued with wonderful fuccefs. Any man who reads the hiftory of difeafes, muft fee that certain fpecies of them appear nearly together in time and place. The order in which they appear, may not be exactly the fame at all times, and in all countries 5 but they oc- cur fo nearly together, as evidently to prove their alliance, and their dependence on the fame general caufes. All popular difeafes muft have, for their caufes, fome princi- ples as extenfive as the effects. Thefe caufes moft probably exift in the elements, fire, air and water; for we know of no other medium by which difeafes can be communicated to whole com- munities of people* Bad food indeed is a fruitful fource of difeafes ; but this muft always proceed from the qualities of the elements which enter into its compofition. A defect therefore in the nourifhing powers of food, is a confequence of a defect or fuperabundance in the elements, or in their combination in animal and vegetable produc- tions. It may be confidered as a difeafe in the animal and veg- etable kingdom, which moft probably proceeds from the fame caufes, as epidemic diftempers among mankind. The principal epidemic diftempers which invade mankind, are, catarrh or influeaza, meafles, whooping or chin cough, the dif- ferent "fpecies of angina, fmall pox, bilious fevers, petechial fe- ver, dyfentery, plague. Of thefe, catarrh is the moft decided* Iy an epidemic dependent wholly on a particular ftate of atmof- phere. Cullen calls it " catarrh from contagion," to diftinguifh it from fporadic cafes of the fame difeafe; but, after careful ob- fervation, during the progrefs of it in the United States in 1789, and again in 1790, I am confident the progrefs of the difeafe de- pends very little on a communication from perfon to perfon. It has been doubted whether it is an infectious difeafe ; and. I have fome evidence to prove it nofcfo ; but certain it is, that its Hid- den invafion of whole families, whole towns and even whole countries, and the rapidity of its progrefs over fea and land, ab- folutely preclude the fuppofition of its dependence on fpecific "contagion. * - " The other difeafes above enumerated may arife from both cau- fes—infection and ^a peculiar ftate of air. Some of them de- pend mort^Vri a1 conftitution of air, fitted to produce them ; othefs/ate feldom produced without a connection with difeafed perfons. It is however proper to obferve that the fmall-pox, dyf- entery arid plague are not ufually, and in ftrictnefs of language, epidemic difeafes. They feldom invade whole countries. They are*more properly endemic ; yet this epithet is not ftrictly appli- cable to them ; being ufed more properly to denote a difeafe XihicKhpeculiar to a particular place, whereas thofe difeafes may invade any place on the globe. The elephantiofis is an endemic in Egypt and certain other places in warm climates j the fmall- pox, dyfentery and plague ufually appear in cities, camps, or 39 other unhealthy fituations, without affecting neighboring places, which contain not the fame local caufes of difeafe. They might therefore, in ftrict propriety, be denominated temporary endemics, in oppofition to epidemics which fpread to all places alike ; and to endemics, which conflantly or vfually appear in particular parts of the world. This diftinftion however is not very material; and I fhall therefore fpeak of the fmall-pox, dyfentery and plague, as epi- demic difeafes ; meaning by this epithet, that they, at certain times, fpread generally over a particular town or region. . Ij The nature^and kinds of contagion will be more particularly confidered, in a fubfequent fection ; the prefent fubject, is, the order, connection, and progreflion obfervable in peftilential epi- demics. The influence of a certain ftate of air in generating epidemics was obferved by Hippocrates, who has defcribed the prevalent difeafes, in different feafons. In his fecond fe&ion on epidem- ics, he defcribes what he calls " Kataftafis Joimodes," a pefti- lential ftate of the air or feafons. He does not indeed in this paflage mention the plague, but he fpeaks of thofe malignant dif- eafes which are, in modern times, the precurfors of the plague, and which are now produced by the ftate of weather which he defcribes. This ftate of the feafons he reprefents thus, " JThe year :$as auftrinus, remarkable for foutherly breezes, rainy and without winds. The firft part of the year dry, and autiumll *a|six>" with foutherly winds, humid and cloudy, In winter, foutherly winds, moiftand mild weather. About the vernal equinox, jte- "vere cold, but the north winds, with fnow, -were of no. long dii* ration. Spring was again calm, foutherly weather—great rains continued till Auguft—then clear hot weather—thecoof Elefi^f winds blew but little and for fhort periods. A rainy autuTtm, with north winds." "■ - The foutherly, hot, humid air here defcribed, whenever q£ long continuance in fummer, proves the caufe of numerous ma-: lignant difeafes, in the United States, as well as in Europe, a|- rho not certainly productive of peftilence. 4Q Hippocrates proceeds to mention the difeafes which prevailed in this ftate of feafons. " Before fpring, even during the cold weather, appeared many eryfipelous difeafes of a malignant type, l)ifeafes of the fauces, accompanied with hoarfenefs, ardent fe- vers', with phrenitis ; ulcers in the mouth ; inflammation of eyes, carbuncfes, &c. Thefe difeafes fpread and became epidemic and mortal." The author then proceeds to defcribe the eryfipelas and other difeafes here named. Thefe cafes differ from the plague in Athens; and prove that the peftilence in Thafus,where he wrote, was of milder fymptoms, though probably cotemporary with that epidemic in Athens. My particular reafon for reciting thefe pa'ffages from Hippoc- rates, is, to prove a progreffivenefs in a peftilential ftate of air, and the difeafes which it prodaces. The difeafes here mention* ed are the fame, fubftantially, as thofe which precede the plague in modern times, in the countries bordering on the Mediterra- nean, and with little variation, the fame With thofe which pre- cede the plague in all parts of the world. Eryfipelous, or other eruptive difeafes, catarrhous affections, or ardent fevers, are the conftant precurfors of the plague, wherever-it appears. Hip- pocrates does not mention any fatal plague, in the ftate of air defcribed ; and.it often happens, at this day, that the ftrength of the peftilential principle is arretted in its progrefs, and the ep- idemics are limited, in their violence, to difeafes of a type lefs malignant than the true plague, or arifing to the plague only in a few fcattering cafes. But whatever may be the degree of the peftilential ftate of the air, or at whatever point, it may be def~ tined to ceafe, and yield to a more falubrious conftitution, the clafs of difeafes which mark its rife and pregrefs, are always fiml- lar, or the fame, modified only in the violence of their fymptoms, by accidental circumftances. A careful attention to thefe facts, cannot fail to convince the obferver of the juftnefs of Sydenham's doctrines, in regard to conftitutions of air ; and the facts themfelves demolifh, at one ftroke, all the common medical doctrines of the communication of peftilence from place to place by contagion, or fomites. Unfortunately, the hiftories of ancient plagues furnifh but 41 little light on this fubject ; yet the barren annals of antiquity and the middle ages, are not wholly dcftitute of evidence to this point. The progreflion of the plague in Rome, growing more general and fatal to the fecond and third year, is a fact re-» corded by Livy, and is related in the preceding pages. The remark of Dion Caflius, that the afhes from Vefuvius, in the great eruption of 79, produced, that year, only flight difeafes, but the next year, an epidemic, has already been no- ticed. It leaves no room to queftion, that the deftructive plague of the year 80, was preceded by epidemic diforders of a lefs ma. lignant type. The middle ages.furnifh facts in confirmation of this doctrin. Witnefs the great plague in 1112, which was preceded by ery- fipelous difeafes in England in 1109, and great mortality in 1111. The plague of 1242, which was preceded by great mortality in> 1240—the fame fact is obfervable in the peftilence of 1252, 1368, 1379, 1390,. 1517,-1527, 1575, 1636—and in many other inftances. This fact did not efcape the notice of that accurate obferver of nature, Lord B_acon, who lived at a period when the plague frequently infefted England. He fays, " The leiTer infections of the fmall-pox, purple fever, agues, &c. in the preceding fum- mer, and hovering all the winter, portend a greatpeftilence the fol- lowing fummer, for putrefaclion rifes not to its height at once." Works, vol. 3, p. 59. That ftate of air which produces peftilential difeafes, Lord Bacon denominates putrefaclion ; but whatever appellation we may give to the caufe of peftilence, the remark is demonftrably well founded, that this " rifes not to its height at once." It is progreffive ; producing firft the " leffer infections." The plague is rarely, if ever, an original, diftinct, ifolated difeafe ; but the laft or moft mortal form of a feries of malignant diftempers. The purple fever mentioned by Lord Bacon is nearly allied to the petechial'fever, which is the ufual precurfor of peftilence in the Levant. The univerfal plague of 1635, 6 and 7, was preceded by the Vol. II, F 42 ufual difeafes, and the progrefs of them is diftinitly traced by the learned Diemerbroeck. He remarks, chap. 3 de pefte, that " the fpring of 1635, was warm and moderately humid, to which fucceeded a very hot, dry feafon, in which appeared many ma- lignant epidemics. In the firft place, a fevere plague broke out at Leyden, and deftroyed more than 20,000 lives. At Ni- meguen, in Gueldres and other regions, a certain peftilent fe- ver fpread with dreadful mortality. In autumn, the fevere heat ftill continuing with exceflive drouth, many other malignant dif- eafes appeared, as fmall-pox, meafles, diarrhea and dyfentery of a very bad type ; but above all, the above mentioned peftilential purple fever, called in Italy petechial, increafed daily in extent and violence, until it turned into the true plague—" donee tandem in apertiflimam peftem tranfiret."—The author goes on to remark that from November through the winter, fcattering cafes of plague occurred in Nimeguen. In January 1636, it increafed, and in March fpread and became epidemic—rofe to its height in April, and continued till October. See pages 5 and 6. • This paflage contains a number of important facts. Firft—the feafons were infalubrious. Secondly—the peftilential ftate of air extended to many places at the fame time : In another page, the author fays "the peftilence fpread over almoft all Germany and the low countries. Thrdly—this ftate of air was of different de- grees of malignity or violence, in different places at the lame time. Thus, the plague appeared at Leyden early in 1635, but cotemporary with this, was the appearance of the purple fever in Nimeguen and in other places ; and during the fummer and au- tumn, this and other epidemics continued to rage with great mor- tality, and at laft, the ftrength of the peftilential principle increa- fing, the fever changed its form, and appeared in the true plague. Now, the modern way of accounting for the plague in Nime- guen, would be to allege or fuppofe fome infected goods to have conveyed the contagion from Leyden, where it firft appeared ; and then to fuppofe the infection to be carried to Leyden from the Levant. The philofophic Diemerbroeck, who was prefent and obferved all the circumftances, fuppofes nothing. He relates plain facts 43 juft a9 they occurred, and admits that the plague muft have ori- ginated in the country. By confidering the malignant epidemics that prevailed at that time, as connected and depending on the fame general caufe, we folve all the difficulties attending the origin of the plague. The petechial fever, which appeared at Nimeguen and other places, in 1635, was one of the forms in which the general contagion of the period, exhibited its effects on the human conftitution. It was a part of the peftilence—it could not be conveyed from Ley- den, for it appeared in moft parts of the low countries and in Ger- many, at the fame time. The fame general caufe, an indifpofi- tion in the elements to fupport healthy life, produced various pef- tilential difeafes, according to place, feafon, age, habit of body and conftitution, until its ftrength and violence arofe to their height, and gradually introduced the worft form of peftilence. The idea of Diemerbroeck, that the purple fever " turned to the plague," muft give great offence to the followers of Mead and Cullen, the advocates for the doctrin of the propagation of the plague folely by fpecific contagion. It oppofes efficacioufly their whole theory, and levels it with the earth. The fact is however indifputable. In the diftrefling period from 1569 to 1577, when Europe was almoft depopulated by the fpotted fever, phyficians obferved that this difeafe frequently turnedinto the plague, and the plague into the fpotted fever. The fame fact was often noticed by writers of the 16th and 17th cen- turies, in which the plague frequently overran Europe.—-Thefe two difeafes, are therefore two diftinct forms or modifications of peftilence—probably bearing an affinity to each other, like that between the diftinct and confluent fmall-pox. This fact fhows that the diftinction made by medical writers, between peflls and peflilentla, the plague and other peftilential diftempers, however ufeful in practice, is not authorized by truth and philolbphy. The ancients clafled all contagious epidemics together, and de- . nominated them peftilence ; and this diftribution, in regard to their caufes and origin, was doubtlefs moft philofophical. The diftri- bution made by modern phyficians, feems to have arifen out of differences of fymptoms, and to be beft adapted to practice, At 44 the fame time, it has probably been the occafion of the common error of confidering different fpecies or forms of peftilence, as difeafes of generical difference, and proceeding wholly from dif- tinct caufes,: when in fact they all have one general caufe in com- mon, and the varieties of their fymptoms proceed from diflincllo- cal and temporary caufes. On this fubject the learned Riverius, in his Praxeos Medicae, lib. 17. has many judicious remarks. He obferves, " That authors, who wrote on fevers, diftinguifh a peftilent from a ma- lignant fever—by peftilent fever they underftand the true plague ; by a malignant one, the fever vulgarly called purple, or other fe- ver, which tho epidemic and contagious, is lefs dangerous, and in which more patients furvive than perifh—whereas the eflence of the true plague confifts in this, that it" deftroys.,njar^jthao.^balf who are feized with it." He however confiders thefe fevers as differing moftly in degree of malignity,- and therefore:frjeats of them under one head. - A peftilent fever this author confiders as not proceeding folely from intemperate heat, or putridity ; but from a malignant and poifonous quality; and whenever this quality appears in a .fever, whether quotidian, hectic or putrid, he thinks it ought to be de- nominated peftilent. A peftilent fever differs from the plague as Jpecies from germs becaufe there may be plague without fever. _ This author remarks alfo the connection between certain epi- demics. " Many deadly difeafes accompany the prevalence of peftilence—as phrenitis, anginas, pleurifies, peripneumonies, in- carnations of the liver, dyfenteries and many others." He af- cribes epidemics to the ftate of air, as a common caufe, to which be adds the ufual local or particular caufes, whkh modify.i^s inv. fluence. .-.;.; Profper Alpinus informs us that thefe difeafes, ^e^ailrajf^in Egypt, at certain times 3.; but he gives no account of their order or connection. Vol. 2. p. 73. # Bellinus defcribes the phenomena which precede the plague, which he calls its antecedents. After mentioning food of a bad quality, impure air from exhalations, intemperate feafons, va- pours emitted during earthquakes and the like, he fays, « Mo^x 45 autem invafuram aBtecedunt moibi epidemici, qui cujuscunque generis efle poflunt, febres petechiales, variolae, morbilli, dyfen- teris, pleuritides epidemicae." De febribus, page 265. This author does not here fpeak of thefe antecedents as unufu- al phenomena ; but lays it down as a general fact, that fpotted fevers, fmall-pox, meafles, &c. become epidemic, juft before the invafion of the plague. Van Helmont obferves that " he could never perceive a differ- ent pulfe in the plague, from that in continual malignant fevers." p. 1138—no incorifiderable authority for the identity of the dif- eafes in kind, however various in degree. The great Sydenham took notice of the unufual prevalence of malignant diftempers, juft before the plague of 1665 In vol. 1, p. L22,Ji£ fays, " I never knew pleurifies, quinfies and other inflarnmatory'difeafes, more common than they were for fome weeks :preeedmg the plague in London in 1665." Thefe were the hybernal and vernal, precurfors of peftilence. As the feafon advanced and the weather became mild, thefe inflammatory difea- fes yielded to a malignant fever, defcribed by the fame author, and already mentioned in the preceding hiftory, which was the immediate precurfor of the true form of the plague, into which it changed by fuch infenfible degrees, that Sydenham himfelf was at a lofs to determin whether that fever was the plague or not, and was candid enough to acknowledge his ignorance. And-a^A further proof that this fever and the plague were only different forms of the fame difeafe, we muft notice the fact recorded by •Sydenham, that when the plague in autumn began to abate, the fame malignant fever- re-appeared—fee page 136 : that is, the difeafe, by change of feafons, began to lofe its glandular marks, and gradually to aflume a lefs malignant type. Hodges mentions thje^me.fe^and fo does'Morton. In every rriftance of a fevere plague* ©'which I can obtain a tolerably correct hiftory, the difeafe has paffed through a fimilat progreflion, arid exhibited fimilar facts. Thus in 1719, the year before the great plague in Marfeilles, appeared a peftilential fever in that city, which, in fome cafes, produced buboes and carbuncles. That is, the plague actually 4$ began W appear, fix months before the arrival of the infeclion from Syria 1 In Aleppo, the plague which appeared in 1742, was preceded by an acute fever ; and after the difeafe abated in July, appeared diarrheas and dyfentery of a malignant type, attended in many cafes with petechx, and intermittents which often proved fatal. Thefe difeafes, in their acute forms,prevailed alfo with the plague, which in this year was not fevere, nor wholly the predominant epidemic. This continued acute fever and pleurifies, ran through the win- ter* In November appeared a few cafes of the plague. Where the Infeclion had lain dormant from July to November, the author of this account, Alexander RufTell, has not informed us. In the fpring of 1743, the plague again appeared and fpread in the city, and at the ufual time in fummer fubfided, being again fucceeded by other acute diforders, which by bleeding and pur- ging, were formed into tertians, double tertians and quotidians. Here again we have the fame progreflion in the ftate of the peftilence, which had been remarked by Hippocrates, Bacon and Sydenham. During the exiftence of this peftilential conftitu- tion in Aleppo, all the ordinary difeafes of the country aflumed a more malignant type ; or as Sydenham remarked of the di£ eafes which preceded the plague of 1665, they " differed from the fame difeafes in other years, by new and unufual fymptoms, which in fhort amounted to this, that they were all more violent.** See vol. 1, p. 20. The difeafes changed their form with the feafons—the acute fever preceding ran into plague, and plague ran into malignant dyfentery, tertians, and other acute diftempers. Similar facts are obferved in America. The plague has been preceded by acute difeafes, as anginas, remittents of a bad type, &c. and followed by remittents, dyfentery and malignant pleurify. The dreadful plague at Meffina in 1743, which deftroyed two thirds of its inhabitants, was introduced by a malignant fever. One phyfician alone out of thirty-three, pronounced it the plague • the others denied it, becaufe the difeafe was not attended with glandular fwellings. 47 A fimilar fever preceded the fevere plague at Venice in 1576, and the fame uncertainty at firft embarrafled the phyficians and magiftracy. The terrible peftilence at Naples in 16^6, was announced by the ufual herald of the difeafe, a malignant fever. One phyfi- cian alone pronounced it the plague, and for his audacity was im- prifoned by the Viceroy. The extenfive peftilence which fpread over all the Levant countries and iflands, from 1759 to 1763, was every where pre- ceded by a fimilar increafe of malignant difeafes, and efpecially by the petechial fever, which appeared, at Aleppo, in the year next previous to the plague. Yet the author of this account, Patrick Ruflel, labors very gravely to trace the difeafe to Turks from Egypt and their old clothes. The uncertainty among phyficians, at the commencement of a plague, with refpect to the nature of the diforder, is a ftrong proof of the doctrin for which I contend. Van Helmont, Diemer- broeck and others have found it neceffary to lay down rules with i great degree of care and caution, to enable themfelves to de- termin, whether a malignant difeafe is the plague or not. Van Helmont obferves, p. 1138 that he could perceive no difference in the pulfe, in plague and continual fevers of the malignant kind —that buboes in the groin, paroitides, &c. are not unfrequently found in fevers free from plague ; and fometimes fpots and car- buncles. But, fays he, if many of thefe appearances do concur, there is no difficulty in pronouncing it the plague, efpecially if they appear before or early after the fever. Diemerbroeck declares, that no one fymptom determines a difeafe to be the plague—neither fever, buboes nor carbuncles are eflential to that difeafe, for it often pafles off without either— \ many of its fymptoms are common to that and other diftempers—- the exiftence of the difeafe therefore is to be determined by a view of all the circumftances, and one criterion, he remarks, is, the prevalence of the plague in neighboring towns. This laft remark indicates that the author had obferved the exiftence of peftilence in various places at the fame time, to be a common event. _4S_ The difficulty at firft in afcertaining the exiftence of the plague, proceeds wholly from the progreffion in the feries of dif- eafes—the malignant fevers, preceding gradually increafing m violence, and changing their form. It has been the fame in the United States. The firft cafes of the bilious plague have occured early in fummer, ufually in July, fometimes in June. Thefe have not excited much alarm, for they have not ufually proved infectious; and they have therefore been clafled among the ordinary difeafes of the hot feafon. This however has ever been a miftake ; they were the lefs malignant forms of approaching peftilence ; yet five or fix weeks after their appearance, when the epidemic has fhowed itfelf in its formidable array, our citizents have hunted out fome veflel from fouthern climates and palmed the evil on her feamen or cargo. Van Swieten, Comment, vol. 16, 3. remarks, " that the plague has fometimes lain concealed under the mafk of other dif- eafes. When the plague raged at Vienna in 1713, it frequently affumed the appearance of a pleurify, catarrh, or quinfy, but foon after, broke out buboes and carbuncles, moft certain figns of the plague, accompanied with the. ufual fymptoms." Here weobferve the ufual precurfors and companions of the plague and the progreffion of the peftilential principle. Hippocrates has remarked the augmented violence of difeafes, in particular periods. He fays, " There are times when almoft all the difeafes that occur, are extremely malignant, and in gen- eral, fatal, fo that coughs, phthifis, angina, are all equally mor- tal. He aflures us, that the truth of his obfervation s hadheen confirmed, in countries very different from each other, and in a variety of feafons and climates." See the-paflage cited in Zim- merman on phyfic, p. 163. We have multiplied proofs of the juftnefs of thefe remarks. Daring the periods which I call peflilential, the common difeafes of a country, as dyfentery, and intermittents, become more obftinate and mortal j aad even the pleurify and peripneumony, acquire unufual violence. And it may not be improper to re- peat an obfervation before made, that the.malignant or epidemic pleurify never appears, except during thefe peftilential periods, 49 It precedes or follows, in winter, fpring or autumn, thofe futrw mers alone when peftilence invades our cities. Such was the dreadful difeafe in America, in 1697-8—in 1761—and which, has fhowed itfelf, in feveral towns, during the prefent peftilential conftitution. But a moft fatisfactory proof of the progreflivenefs in a pefti- lential ftate of air, and in the correfponding malignity of dif- eafes, is found in the bills of mortality. Thus,, before the Lon- don plague in 1625, the bill of mortality rofe from 8 or 900a, the ftandard of health, to 11,000 in 1623, and to 12,000 in 1624. The approach of peftilence was clearly announced, two years before it appeared. And as the time of its appearance drew near, the extenfion or malignity of the preceding fevers was greatly augmented ; for in the year of the plague, almoft nineteen thoufand perfbns died of other difeafes than the plague. As the plague ufually prevails from June or July to November^ and other difeafes are moftly merged in-it, almoft all the deaths by common difeafes muft have been in the beginning of the year, from January to June or July. Now, eighteen thoufand deaths in the fix months preceding the plague, or even two thirds of the number, mark a prodigious increafe of mortality—the common fign^ of approaching peftilence. In the peftilential period in London, from 163410 1636, the bill of mortality rofe two years previous to the plague. The Iaft great plague, in 1665, was announced by unufual malignity in difeafes, four years before its appearance. In"i66ii according to Sydenham, began a feries "of epidemics, which greatly fwelled the lift of burials. There was however fome a- batement in 1663; but-in 1.664, and the firft five months of 1665, the mortality again increafed with rapidity, till a dread- ful peftilence laid wafte the city. A fimilar increafe of mortality is obfervahle in the bills for Augfburg, previous to the plague in 1628, and in 1635—in Drefden, in 1632 and 3—in Philadelphia in 1793, in New- York in 1795, and in New-London in 1798. It muft however be obferved, that the bills of mortality wiij Vol. II. ....... G 5« not, in all cafes, exhibit the augmented number and malignancy of the difeafes which precede peftilence ; for it fometimes hap- pens that the year next preceding the plague, is very healthy, and the malignancy in the diftempers, which mark the beginning of the* peftilential ftate, does not appear till the winter or fpring previous to the plague. In this cafe, the augmented mortality falls within the year and the fame bills, as the deaths by the plague. This was the cafe in Augfburg in the year 1535. In fuch cafes, there is an interval between the preceding epidemics and the plague ; fuch as we have obferved in the New-England States, between the influenza and the fcarlet fever, and the lat- ter difeafe and the yellow fever. Monthly bills will exhibit the progrefs of peftilential epidem- ics, with more accuracy. Fernelius remarks page 161, that " infection is to be perceiv- ed in the air, when it produces fevers not peftilent, but which are at the threfhhold of peftilence,"—plainly intimating that cer- tain malignant difeafes precede the plague. He fpeaks of the fact as general and well underftood. Even in the Weft-Indies, the infectious yellow fever has its pre- curfors. That fever in Barbadoes, in 1738, was preceded by catarrh and fuffocating cough in 1737 and fpring of 1738. Yet authors pretend the difeafe to have been imported from Martinico ! See Warren and Short, vol. 2. 164. The different modes in which peftilence invades mankind, feem to depend on different caufes. Sometimes, the principal caufe feems to be an effential alteration in the invifible properties of the elements ; in which cafe, the difeafes of a particular con- ftitution, thofomewhat modified in their fymptoms, are not con- trolled or arrefted by the feafons. On the contrary the atmofphere continues to be peftilential, and to multiply diforders of a ma- lignant type, through every variety of feafons and of weather. Thus, we obferve many inftances of violent plagues in the moft pleafant, and to all appearance, the moft falubrious feafons. Several inftances have been mentioned in the preceding hiftory and we have demonftration of the fact in the United States. The prefent peftilential ftate commenced with the meafles and $1 catarrh of 1789 and 90.—The fummers of 1794 and of 1797 were apparently temperate and falubrious ; yet in both thefe fummers, the plague renewed its ravages in fome towns, tho with lefs mortality than in the fultry and unhealthy fummers of 1793-95 and 98. On the other hand, peftilence fometimes proceeds principally from exceflively intemperate feafons, as in fevere heat, after a cold winter. In this cafe, the peftilence may invade a city very fuddenly and without a regular augmentation of mortality from previous difeafes. But even in this cafe, the plague has its precur- fors, which appear at leaft a few weeks, if not two or three months previous to its attack. Thus the plague in Aleppo in 1742, firft fhowed itfelf in the fuburbs in April ; but was preceded by an acute fever in March. The bilious plague in Philadelphia in 1793, according to Dn Rufh, was preceded by the influenza, fcarlatina and bilious re- mittents. The fame difeafe in 1797 appeared, in fcattering ca- fes, as early as June. In New-York, the epidemic of 1795 was preceded by an- gina trachealis with anomalous fymptoms, fome cafes of obfti- nate dyfentery, at a premature ftage of fummer, and by febrile complaints accompanied with bilious evacuations. At a meeting of the medical fociety, early in July, thefe facts were mentioned, as denoting an uncommon ftate of air, asd the fociety came to a refolution, to make particular obfervations on the difeafes that might occur, before their next meeting. But, in the interval, the crifis of the peftilence arrived, and removed all doubts. See Dr. Baily on the epidemic of 1795, p. 55, and fequel. The fevere peftilence of the year 1798 doubtlefs owes its vio- lence to a feries of moft intemperate weather—moft exceflive heat, following a long and feverely cold winter. Yet this dif- eafe was preceded by premonitory figns, efpecially catarrhal fe- vers. Of all the diforders to which mankind are expofed, none feem to jndicate a peftilential ftate of air, with fo much certainty as catarrhalVffections. They almoft always precede the plague —ufually accompany it, and fometimes tread clofe upon its heels. In addition to the numerous authorities already cited, in proof JL of the progreflion of peftilence, let me mention Skenkius, who, infpeaking of the difeafes of 1564 and 5, obferves, that angi- nas, pleurifies and peripneumonies became epidemic ; abortions were frequent, pains in the joints, fmall pox and meafles " quos tanquam praecurfores fequebatur epidemica lues, incredibili graf- fationis faevitia," depopulating towns and country, in Turkey, Egypt, France, England and Germany. Obfervations, p. 748* Skenkius remarked that the plague followed the other epidem- ics, as its precurfons. The fame author takes notice of a malignant angina, in 1564, which often proved fatal in a few hours, like the plague. I men- tion this, becaufethe learned Dr. Fothergill, and tribes of mod- ern phyficians who follow a celebrated name, have alledged that the angina maligna is a new difeafe, not known in Europe till.a- bout the year 1610, altho it never was more fatal, than in England in 1517. In 1573 prevailed dyfentery, meafles, and purple fever, which in 1574, fays Skenkius, changed into the plague. His words are remarkable. " Dudum fane praefagiebat animus mihi, malignum hoc febrium genus, quod toto bienflio Europae partem non mini- mam peragravit, velut fparfis quibufdam praehidiis, in peflem aper- tiflimam tranfiturum. Neque me adeo meafefellit opinio." Ob- ferv. p. 761. This author forefaw the plague, bymeansof its precurfors. " Eodem modo variolas, morbilli, dyfenteriae groffantes, f Swieten, vol. 16. 47. Such was the fact in the days of Thucydides. Numerous obfeivations on thefe phenomena lead me to fufpect, that the electricity which is to produce the explo- fion, is in action for a confiderable time before the fhock, and that it is this previous aSion which occafions epidemic difeafes. That is, the ftimulus of fire or electricity produces fenfible effects on the bodies of animals the more fufceptible objects, before it does on the lefs fufceptible fubftances in the bowels of the earth. The earthquakes do not always occur in the feat of the pefti- lence. I find no concuflion mentioned to have happened at Lon- don in 1665, or in the years next preceding or following ; but fhocks were experienced in the neighboring counties in 1665, and 1666. This feems to have milled the able Diemerbroeck, who, in rea- foning on the caufes of the plague, objects to the influence of earthquakes, becaufe no fhocks occurred at Nimeguen, before the peftilence of 1636. It is probably true that earthquakes are not ufually the caufe of the plague ; but that they have fome con- nection with the caufe, I can hardly doubt. The miftakes of Diemerbroeck and others on this point feem to have arifen from confidering the plague as an ifolated difeafe, and as depending on a caufe local and temporary ; whereas a juft view of the fubject muft comprehend all the difeafes of increafed malignity which precede the plague, very often for two or three years. Such a view alfo muft include, among the caufes of the difeafe, the agitations or derangement of the elements in remote parts of the country. Thus, altho no earthquake was experienced at Nime- guen, about the time of the plague, yet a fevere fliock was felt at Laufanne in 1634—Keyfler's travels 190. This marked fome general action of internal fire, which, tho it might not explode fo as to fhake all Germany, might have produced effects, by means of an infenfible vapor or ftimulus, in all parts of Europe. Certain it is, that for the period between 1631, the year of the tremendous eruption of Vefuvius, and the year 1637, all Eu- rope was afflicted with mortal epidemics. The philofopher who would obtain juft views of the caufes, muft extend his inquiries to JL all the great phenomena, which occurred during this whole peri- od, in all Europe at leaft, if not in the American hemifphere ; for fuch a view only will comprehend the whole extent of the peftilential ftate of the atmofphere. It muft Hot be forgotten, that during this period from 1633 to 1637, when the plague or other defolating difeafes, fpread over both hemifpheres, Etna was in a continual ftate of eruption ; as it was for fifteen years, during the peftilential conftitutions def- cribed by Sydenham in his days. In looking over the lift of comets, and the hiftory of earth- quakes, I am compelled to believe the approach of comets to have no fmall influence on the electricity and fubterranean fires of the globe. Such a vaftly great proportion of the violent concuflions of the earth have happened, within a few months of the appearance of comets, that no reafonable man can fuppofe the coincidences to be the refult of accident. Equally remarkable have been the coincidences in time be- tween the appearance of comets and the explofions of volcanoes, And this fact is no trifling confirmation of my opinion, refpect- ing the influence of comets in producing earthquakes ; for earthquakes and eruptions of volcanoes are often cotemporane- OH3.* * It is not only during the appearance of comets, that their effect* are perceived in the elements, but for many months before and after. I can teftify from careful obfervations that the effects of that in Auguft 1797, were very obvious, in anomalous tides, as early as the laft week in May; and the inundations in England during the autumn and win- ter following, fhow its effects feveral months after its dtparture. The whole hiftory of comets and their effedts warrants this conclusion. Seneca made this remark Seventeen centuries ago. Thefe are his words. " Ariftoteles ait, cometas fignifkare tempeftatem et ventorumintem- perantiam atque imbrium.—Non ftatim cometes ortus ventos et pluvias minatur, fed totum annum fufpeBum facit.—" Ariftotle obferves that comets indicate ftorms and violent winds and rain.—Thefe effects how- ever do not immediately follow their appearance, but are to be expe&- ed, during the whole year " He then mentions that fuch was the facl, with the comet predicted by Ariftotle and Theophraftus, and which appeared in the confulfhip of Paterculus and Vapifcus. Nat. Queft. lib. 7. I would further obferve that comets move in trajectories of an elip- lical or parabolic form, the fun being fituated in one of the foci. The time when we obferve them is when theypafs this part of the ellipfis. Now according to the univerfal law of planets, by which they defcribe equal areas in equal times, their motion muft be moft rapid when near- eft the fun, and within our Gght. Before their appearance, and after 88 I cannot however admit, that the explofions of fubterraneaa fires, are the direct exciting caufe of peftilential difeafes. It is indeed afcertained, beyond all queftion, that periods of exten- five peftilence and mortality are remarkable for earthquakes and eruptions of volcanoes. But the explofions of fire do not fo generally precede epidemic difeafes, as to authorize the fuppofi- tion that they produce thofe difeafes. Earthquakes occur, dur- ing the prevalence of peftilential or other mortal epidemics, but in the midft of the period, or fometimes at the conclufion. Hence I deduce an opinion, that peftilence and earthquakes depend on one common caufe ; which excites into action the in- ternal fires. But I fuppofe the action or fermentation may pre- cede, for months and even years, the explofion in earthquakes and volcanoes and by means of an infenfible vapor, or heat or electrical difcharges, the elements of water and air may be eflen- tially affected, in fuch a manner as to impair the principles qf animal and vegetable life. Whether this is a juft explication of the caufe, may be a queftion ; but fo many phenomena concur to authorize it, that I cannot withhold ray affent to the general principle. The fame effect perhaps may be produced by the exceflive ac- tion of jnere ftimulus upon the animal fyftem, without the infu- fion of a deleterious vapor into the air. A remarkable evidence of the effects of fire or electricity on the earth and air, before its explofion, is the extreme drouth which is often experienced over whole continents or the* their 'departure, their movement is flower, than when within the fo- lar fyftem, and they may be near the earth, many months before they enter the fyftem or become vifible. Hence their influence on the earth fo long before and after their appearance. It is further to be obferved that many comets doubtlefs enter the fyf-"' tcm and pafs round the fun without ever being fcen, and fuch as come from regions of fpace directly oppofite to the earth, muft be invifible', unlets wc can fee them in the fplendor of the fun's rays. This re- mark is as old as Seneca and older. He relates an inftance, in which Pofidonious difcovered a comet, in the darknefc of a folar eclipft, which would not have been feen, had not the eclipfe happened. xLib. 7. feet. ao. Newton and Halley have made the fame remark. Heuce perhaps we may account for violent feafons, like the fevtre winter of 1780, which happened without the appearance of any comet. This is mere coii- icctur;. 89 whole world, for fix and even twelve months antecedent to a great eruption of volcanoes. In confirmation of my principle, that the changes in the ele- ments producing epidemic difeafes, are effected by the all-perva- ding action of electricity, the ufual appearance of meteors or celef- tial lights, in peftilential periods, muft be mentioned. For the truth of the fact, we have ample proofs in every age. The in- ftances of meteors or other celeftial appearances of fire, which are recorded of peftilential periods, are fo numerous, as to leave no room to queftion the connection between the caufe of peftilence, and the fire that belongs to the fyftem. Sometimes thefe fiery ap- pearances are ftationary lights in the fky, which the frightened im- aginations of men have formed into armies ready for combat, and confidered as the preludes of bloody battles. Sometimes the heavens have been filled with thofe fmall meteors, called falling or fhooting ftars. At other times immeBfe globes of fire have traverfed the celeftial regions, and burft with a tremendous report.. During a plague in Vienna in 1679, ^ays Van Swieten, vol. 16. p. 19. from Sorbait, feveral bluifh fiery balls were feen in the air, fome of which fell and fenfibly increafed the heat. In October 1709, when the plague was in Dantzick, a blue fiery globe came from the north weft and fhot over the town with amazing celerity, illuminating the town and falling at the fouth- ward. Baddam's Memoirs, vol.6. 14. During the plague in Philadelphia in 1793, about the 12th of September, a meteor fell between the city and the hofpital. Rufli. p. 108. During the extreme heat which introduced the peftilence of the laft fummer, 1798, about the 9th of Auguft, the fmall me- teors or falling ftais were incredibly numerous, for feveral nights. They almoft all fhot from the north-eaft to the fouth-weft, and fucceeded each other fo rapidly as to keep the eye of a curious fpectator almoft conftantly engaged. Diemerbroeck remarks that during the fummers of 1635 anc^ 6, at the time of the fevere plague in Holland, there was a vaft number of ardent ftars, gliding through the celeftial regions and Vol. II. M 9o falling to the earth. " Stellarum ardentium in Ccelo oberranti- um magnus concurfus, et in terrain prolapfio." He mentions likewife almoft continual flafhes of light, in a ferene flcy, or fi- lent lightning. Livy mentions that the heavens appeared to be in a flame, pre- vious to the fevere peftilence of the year 290 from the building of Rome. A flame in the heavens is noted under the years, 733, 742 and 788, all which were peftilential. This flame is not defcri- bed, and whether it was of the fpecies of Aurora Borealis, which extended over the celeftial region, or of that fpecies of light, or yellowifh red colour, which diftinguifhes our modern dark days, cannot perhaps be determined. But a curious phenomenon of this kind happened in the fevere winter of 1741, which was too remarkable to be paffed over in filence ; efpecially as it may pof- fibly explain what Livy and many other hiftorians have recorded, that at certain times, " it rained blood." The aflertion is often found in hiftorians of credit, and has by the moderns, been num- bered among the extravagancies of popular credulity. But an appearance which would warrant fuch an aflertion occurred in this country, and is ftill recollected by old people. In the month of January 1741, in the midft of one of the coldeft winters of this century, there was a little relaxation of the rigorous cold, during which the heavens were overcaft with clouds and a little rain fell. Late at night, during this falling weather, the heavens appeared all in a flame, fo bright as to illu- minate the earth and render objects every where diftinctly vifi- ble. Many people faw it and were alarmed, fuppofing the great day was at hand. The rain which fell during this light, had precifely the appearance of d/ops of blood diftilling from the clouds. This relation is taken from my father, who was then nineteen years old, and recollects all die circumftances more minutely than the events of the laft year. The well known dark day in May 1780, was diftinguifhed by a fimilar light in the heavens; but not occurring in the night, it was lefs an object of wonder. 9* I ftrongly fufpect a fimilar phenomenon will account for thofe paffages in many hiftories, which fpeak of raining blood, and ena- ble us to do juftice to the veracity of the writers. Appearances of this kind have ufually occurred in periods of peftilence, when the imaginations of men have been fubject to alarm ; and they have often happened during extraordinary fea- fons. The light of 1741, was during a moft fevere winter, and in the moft fickly period, thatfchas occurred this century. See the London bills of mortality. In America, that winter was followed by peftilential difeafes. The dark day of 1780, was on the opening of fpring, after a moft fevere winter, and altho that year was not fickly in general, yet in the year following, we had an epidemic catarrh, fucceed- ed by a feries of epidemic difeafes of other kinds. It is remark- able too that on that very day began a violent eruption of mount Etna. In 1716, in the month of October, happened a dark day; this was after a moft fevere winter in Europe. I have no ac- count of the feafons in America, but the next winter was unufu- ally fevere, and fnow fell in extraordinary quantities. On the 9th of Auguft 1732 happened another dark day. This was followed by earthquakes, a fevere winter and univerfal catarrh. The 19th of October 1762 was equally remarkable for dark- nefs, with the phenomenon of a red, or yellowifh tinge in the heavens, which gave to the fun, when it appeared, the color of blood. Some rain fell during the day, and the water was of a dirty fulphurous fmell. There had been two earthquakes, with epidemic catarrh, in America in 1761. In the fame year with the darknefs, 1762, the catarrh was epidemic in Europe ; and the winter of that year was exceflively fevere in both hemif- pheres. A comet appeared in 1762 and an eruption of Etna followed the fevere winter, in 1763. There were earthquakes alfo in Afia in 1762. Who can doubt that the vapor, occa- fioning fuch darknefs, is the effect of the agitation of the fire of the globe ? Similar inftances of extraordinary darknefs have occurred 10 92 every age. They are mentioned in the years before Chrift 366 and 295—and of the Chriftian era 252, 746, 775, and in ma- ny Other periods. And the reader will obferve, tliis darknefs is cotemporary with peftilence, in almoft every inftance. Du- ring the plague of 746, the darknefs was of feveral days dura- tion—in 252 it was of three days, and in 775 of fix days con- tinuance. A fimilar darknefs accompanied the peftilence in E- gypt, in the days of Pharaoh. TOany other inftances have been mentioned in the preceding hiftory. In America, it has been cuftomary to afcribe this unufual ap- pearance to condenfed volumes of fmoke, after the burning of immenfe tracts of woods in the weftern parts of the country. But I cannot learn that any great fires have ufually preceded thefe dark days ; and negative evidence, in fo many inftances, amounts to proof that no great forefts have been burnt. Befides, the fame phenomenon has been often obferved, in countries where there were no forefts, as in Italy, Syria, Afia Minor and Egypt, and efpecially in England. That the fmoke of burning forefts cannot be the caufe may be rendered very certain by thefe considerations. Firft, the caufe is not equal to the effect. Had the woods from the 40th de- gree of latitude in America to the 50th been all confumed in* a day, the fmoke would not have been fufficient to cloud the fun over the territory covered by darknefs on the 19th of May. Any perfon may judge of this who has feen large tracts of foreft on fire. That thirty or forty miles of burning foreft, fhould cover five hundred miles with impenetrable darknefs, is too ab- furd to deferve a ferious refutation. In the fecond place, the color of fmoke, when elevated into high regions of the atmofphere, is very different from that of the vapor which caufes the darknefs on all fuch occafions. But what decides this queftion is the lightning, thunder and rain, and efpecially the meteors that accompany thefe clouds of vapor. As far as I can learn, fome or all of thefe phenomena attend dark days. Thunder was heard on the mornin" of the 19th of May, in moft places. Mem. Am. Acad. vol. 1. 238. Violent thunder fqualls and a meteor followed the great darknefs 93 in Canada in 1785. Thefe phenomena demonftrate that the cloud6, on fucli occafion, have a connection with electricity. This is further evidenced by the fmell of fulphur, in the water that falls, and the fcum that is left on objects—fmoke would not produce either; nor would the Lirgeft volume of fmoke ever raifed into the air, fpread over an extenfive region, a denfe fub- ftance that fhould become vifible and tangible on the earth. Be- fides this darknefs or vapor ibmetimes occurs in winter, when the earth is covered with fnow. When we connect with thefe facts, the circumftance that thefe dark days always occur, during or near the time of volcanic eruptions, earthquakes, or the unufual feafons which accompany peftilence and epidemic dieafes of other kinds, we fhall be at no lofis to charge them to the account of the central fires, or the difcharges of electricity. This accumulation of vapor is not a more furprifing phenomenon, than the fudden chaBge in the properties of the atmofphere which produces univerfal catarrh. Hodge, who wrote on the plague of London, and who ap- pears not to have been rewarded with celebrity equal to his mer- its, fuppofes the caufe of peftilential difeafes to be a fubtle aura,or vapor exhaled from the bowels of the earth, which has, by too much heat and humidity, loft its wholefome qualities. He fays, in proof of his opinion, that a given quantity of earth, infufed into water in fpring, depofits more fait than at another time of the year. His idea feems to be not very different from that of Van Hel- mont, who fuppofes the caufe of peftilence to be a gas or air, which has putrified by continuance, as the tranflation is ; by which is meant, probably, a ftagnation in the earth. The doctrin of an infenfible vapor, infufed into the atmof- phere from the bowels of the earth, may perhaps be thought wholly conjectural. But there are fome phenomena which can hardly be refolved without reforting to the action of the electrical fluid. The fudden changes of weather cannot be accounted for, in all cafes, by changes in the winds. Indeed the moft reflect- ing philofophical men acknowledge themfelves puzzled to aflign reafons, for many of the rapid tranfitions from heat to cold and 94 from cold to heat. It has been fuggefted, that the heat may afcend and defcend in the atmofphere, by means of phyfical laws, to us unknown ; but this fuppofition is not fupported by any clear proofs, perhaps not by rational probabilities. There are many' reafons which incline me to believe that the principle of fire, the moft fubtle, penetrating, active fluid in creation, and unqueftionably the moft powerful agent in all the movements of matter, paffes more frequently and rapidly from the earth into the atmofphere and vice verfa, than is commonly imagined. I fufpect that an intimate connection fubfifts in this Tefpect, between the interior of the glebe, and the atmofphere which furrounds it. To the rapid palling of heat from the earth to the air, and from the air to the earth, we may perhaps afcribe many of the amazing changes which take place in the temperature of the air, in a few hours, and often without a change of wind. The increafe and the moderation of cold are fometimes very obvious, long before the change of winds to which we ufually afcribe fuch changes ; and I fufpect that the changes of winds are more fre- quently the effctl, than the caufe, of a change in the temperature. But there are fome appearances, in the atmofphere, previous to fhocks of earthquake, which demonftrate a clofe connection between the atmofphere and fubterranean fire. A remarkable one in this country, and generally in others, is a univerfal feren- ity and'tranquillity in the atmofphere. The fky is cloudlefs, and all nature, if at night, is wrapped in profound filence. This phenomenon is too uniform a precurfor of earthquakes, to be deemed an accidental circumftance. It muft be an effect of fome connection between the air above, and the caufe of earthquakes. It is remarkable alfo that feamen fometimes obferve a fwelling of the ocean, without wind, and before any fliock of the earth; and this fact, Pliny mentions among the figns of an approaching earthquake.* The fame author mentions a well known fact that Is not this fwelling of the ocean, previous to an earthquake, anal- agous to the tides ? May not both be afcribed to the force of electricity; tke fwell of the water preceding earthquakes beiDg irregular, as depend- ing on no regular vifible caufe; and the tides being more regular, as be- ing the effect of the mooa's influence on the eledtrical principle Thi« idea feems to derive fome ftrength from the known fait that earthquakes 95 fometime before the concuffion, birds appear to be greatly agitat- ed, and retire. In Italy, a common prelude of an earthquake is, a thin white oblong cloud or vapor, nearly refembling the color of wool. This fign was feen for feveral days in the year 1702, before the earthquake. The fame was obferved by Caf- fini in 1668, in the fame part of the heavens, the fign of the whale. See Pliny, lib. 2. 81. Baglivus, page 543. The evening before a violent earthquake in Sicily in 1693, a bright flame was obferved, apparently about a mile diftant from the fpectator ; this flame vanifhed as foon as the fhock occurred.* The day fucceeding the firft fhock, the fky was darkened, and tinged with a deep yellow. This was the prefage of a moft tre- mendous concuffion, which demolifhed many towns in Naples, Sicily and Malta, Seneca relates that a violent earthquake in Campania, altho in winter, was preceded by a calm of feveral days duration. Nat. Queft. lib. 6. 12. For fometime before the great earthquake in Italy in 1638, the air was perfectly calm, and the heavens ferene, butthefea was covered with little bubbles, as if agitated by drops of rain. The phenomena that occurred in Germany and Holland, on the day, but not at the hour ©f the tremendous earthquake ufually happen in periods of the moon's revolution, when that orb ex- erts its greateft influence on the earth. From numerous calculations, it appears that earthquakes ufually occur near the moon's perigee or apogee or the change or conjunction of fun and moon ; generally about three days before or after the conjunction—this, by the way, is the very time when epidemic difeafes ufually invade the patient, or come to fatal termination, according to the remarks of all modern phyficians —a lingular faet that may lead to important conclufions. In a few inftances, earthquakes happen near the full moon—the oth- er pofition in which that fatellite exertstnore than her ordinary influ- ence on the earth. Let thefe facts be compared with the occurrence of violent tempefts about the fame time of the moon's revolution, the invafion of epidemic difeafes and the full tides. A ftrong confirmation of this opinion is derived from the fwelling of thefea, juft before a hurricane in the Weft-Indies. There is a vifi- ble intumefcence, before the atmofphere is clouded, or the leaft breeze of wind. What can be the caufe, but the electrical fluid which is paff- ing from the earth to the atmofphere, and is fpeedily to produce moft tremendous effects. See the Addenda. • A fimilar light was feen at Derby in Connecticut, in the evening preceding a local explpfion of fire, about thirty years ago. 96 which demolished Lifbon in 1755, were very remarkable. The water was violently agitated, buoys were broken from their chains, large veffels fnapped their cables, fmaller ones were thrown afhore, boats in canals were forced from their faftenings, chandaliers vibrated in the churches, water in fmall veffels was agitated and dafhed over the fides ; and all this without any fen- fible motion of the earth or buildings. See Encyclopedia, art. Earthquake. Thefe phenomena indicate a connection between the atmo£ phere and the fubterranean fire, which is altogether invifible, and to men, imperceptible. We perceive nothing, before the fhock but univerfal ferenity and calm ; but the delicate fenfes of the fowls of heaven are affected ; they fly about in a fright and ap- pear to want the ufual fupport from the air. The waters of the ocean alfo fwell, altho no concuflion of the earth or water can be perceived. Do not thefe phenomena indicate, either a want of the ufual weight or elafticity of the air ? Or what defect is there in the mafs of air furrounding the earth, which is to be fupplied by an explofion of fubterranean fire ? That there is a connection or dependence of the fire above on that beneath the earth, and ' that this fubtle fluid acts and reacts between the earth and the air, with a rapidity and a force beyond all calculation, is to me extremely probable. The appearances that precede earthquakes indicate, that the fire which is to produce the fhock, is in vio- lent action, for a confiderable time, before the fhock. For fev- eral days before the earthquake at Oxford, Sept. 17, 1683, ignes fatui, luminous appearances, were frequently feen. Baddam's Memoirs, vol. 2. 208. It fometimes happens that hot fprings burft forth before earth- quakes ; and miners perceive heat in the earth. Often have earthquakes been preceded by a perturbation, 2 ftench, or difcoloration of the water in wells aRd fprings. Sometimes the water in wells and rivers recedes or is evapo- rated before the explofion. It is faid that Pherecydes once pre- dicted an earthquake in Lacedemon, from the difappearance of the water in a well. Pliny, Nat.Hift.lib. 2.79. The rivers and fmall ftreams in Iceland arv, obferved to be- 97 come entirely dry for fome weeks before an eruption of Heckla, as was the cafe in 1783. Meteors alfo, earthquakes and fome- times flafhes of lightning precede or accompany the eruptions. See Van Troil's Letters on Iceland. The various founds or noifes which precede and attend earth- quakes, are a ftrong confirmation of thefe ideas. The ufual premonitory found is compared to the rattling of carriages on a pavement. Sometimes it is defcribed, as the rumbling of diftant thunder. But in truth the found is different at different diftances, and refembles no other found in nature. It is alto- gether fui generis. It is moft analogous, when near, to the rat- tling found from a near explofion of the electrical fluid ; as thofe can teftify who have been near the place where lightning has fal- len upon objects. It bears no refemblance at all to any artificial founds, made by the explofions of gun-powder, or other human contrivances. It is moft unqueftionably the effect of the elec- trical fluid, rufhing from one part of our fyftem to another—- probably from the earth to the atmofphere, to reftorc the equili- brium, which has been, by fome means, deftroyed, or to anfwer other unknown purpofes. This idea correfponds with the mod- ern theory of earthquakes, which afcribes them to the electrical fluid. See the Encyclopedia, art. earthquake. Let it be ob- ferved that at fea, no found precedes an earthquake ; water be- ing a good conductor of electricity. Eruptions of volcanoes have alfo been preceded many weeks by a vifible fog or vapor, fufpended over the mountain, as hap- pened before the great difcharges of Heckla in 1783. To what caufe fhall we afcribe this, but to the action of fire which pre- cedes the explofion ? And if a vifible vapor may be extricated by this action, for months before the explofion, of which we have certain evidence, why may we not fuppofe, a fmaller action or force to expel an invifible vapor, in any place and at any time ? Other facts authorize this conjecture. On the 12th of Sep- tember 1784, the water of the Loch Tay in Scotland, fuddenly receded 300 feet and left the channel dry ; then returned ; con- tinuing this vibration for every feven minutes for two hours, and at the fame hour in the day, for a week, with lefs violence. Vol. II. N No wind was ftirring, and no vifible caufe could be afligned for this novel phenomenon. To what caufe fhall wc refort for a folution, but to the invifible energy of electrical fire ? Sinclair, vol. 6. 623. If we admit then the action of electricity to be the caufe of earthquakes, we fhall have reached the general proximate caufe of thofe epidemic difeafes which fpeedily fucceed concuflions of the earth. The caufe muft be the atfion of fire, the moft ener- getic principle in nature. The manner in which this effect is produced, whether by forcing an unwholefome vapor from the interior of the earth, and vitiating the atmofphere; or whether by fimply changing, on mechanical principles, the proportion of oxygen contained in atmofpheric air, or by mere ftimulus or other unknown means, is a queftion of a curious nature, and worthy of philofophic investigation. One thing is very evident, that what I denominate a peflilen~ tial principle, does, at certain times, pervade not only the ele- ment of air, but the water alfo. The proofs of this are abun- dantly numerous and convincing. In all the great plagues which have afflicted the human race, other animals, as horfes, cattle, lheep, fometimes cats, dogs and fowls, together with the fifh in rivers and the ocean, and even vegetables, have borne their fhare in the calamity. The peftilential principle has extended to every Ipecies of life. The beafts of the field perifh with deadly epi- demics ; the fifh die on the bottom of rivers and the fea, or be- come lean and fickly; while corn is blafted on the moft fertile plains, and the fruits in gardens and orchards, wither or fail to arrive at their ufual ftate of perfection. In the deftructive plague which defolated Italy in the time of Romulus, Plutarch and Zonaras mention a general ftcrility of the earth ; the very trees were affected, and all nature appeared to be defective in its powers of production. In the beginning of the peftilential period, in the reign of Juftinian, Baronius ftates that corn was deficient in quantity, and defective in its nourifhing qualities. About the year 1600, crops failed in all parts of Europe ; as they did in both hemifpheres, about the clofe of the laft centu- 99 iy. Such was the cafe in 1740, in fome parts of Europe ; and in 1766. The failure of grain in India in 1770, and in 1783 and 1789, are ftill remembered ; and in fome of thefe inftances, the crops failed, at the fame time, in China, India, Europe and America. When exceflive rains or dry feafons precede this failure of crops, men are at no lofs to aflign the caufe; altho, in thefe ca- fes, they may fometimes miftake the true caufe. But it often happens that grain fails of its ufual perfection, in feafons appa- rently the moft temperate and faijorable. Obferving farmers re- mark that, in certain years, when blaft or mildew is expected from intemperate weather, grain proves to be good; at other times, the grain will fhrink very much, under a feries of weather apparently the moft propitious. This has been obferved in Fair- field county, in Connecticut, where the excellent lands formerly produced great crops of wheat, with as much certainty as any other grain ; but within a few years paft, wheat has failed, with- out any apparent caufe. In fome cafes, the farmer fcarcely re- ceives his feed, altho the feafons are favorable and no infect ap- pears.* The failure of certain fpecies of fruit-trees and flirubs is a fact equally remarkable. Some kinds of apple, for a few years paft, have been fmall, kaotty and fprinkled over with fpecks. The plum-tree has become full of warts, or bulbous excref- cences, which kill the tree, and in fome parts of our country, bid fair to extinguifh the fpecies. Thefe have been fufpected to proceed from a fly or fmall worm ; but on examination by a mi- crofcope, I find reafon to queftion this fact. Some of the ex- crefcences contain a fmall white worm, about a line in length ; but they perforate the wood after the excrefcence is formed, as appears by their path ; and fome of thefe warts contain no infect whatever. The infect therefore finds a nidus in the excrefcence, but is rather an effect, than a caufe. The burfting of the bark is a difeafe, which feems to have begun or been very much in- creafed, during the prefent peftilential period. * The fame was the cafe in all the eaftern ftates for three or four years; but in this fummer, 1799, the wheat has every where a full grain. IOO . Iha peach-tree has, within a few yeais, been particularly fub- ject to be deftroyed by a worm, which attacks it juft below the furface of the earth, and feparates the bark from the wood. If this is a common evil, ftill the vaft increafe of it, at particular periods, is among the phenomena of peftilence. The locuft is perifhing by a fimilar malady. Cotemporary with thefe difeafes of the plum and the peach, has been a diftemper of the pear, ufually called the pound pear, one of the moft delicious of the fpecies. For eight or ten years paft, that fruit has been, univerfally in the part of the country to which my obfervations have extended, fubject to a blaft, from a fpecies of ruft which covers a large portion of its furface. In my own garden, not one in five is fit to cat; but I have feen one gentleman in a neighboring town, who thinks the pear is begin- ning to recover. The univerfal death of the prim is a phenomenon ftill more extraordinary, and a moft fevere calamity. The town of Eaft- Hampton on Long-Ifland, loft, in 'two or three years, two hun- dred miles of hedge—a greater lofs, fays Mr. L, Hommidieu, in a paper publiflied among the tranfactions of the New-York Agricultural Society, than if every houfe in the town had been burnt to the ground ; as no proper fubftitute for fences has yet been difcovered. The Englifh black thorn has been tried, but has failed, owing to a fly that perforates the bark. See part 2. 103. The caufe of the death of the prim is not known, nor the precife time when it began. But in Connecticut the failure was obferved about twenty-five years ago ; between the years 1770 and 1777, during the prevalence of the terrible angina and dyf- entery among men. It contiuned gradually to extend for fome. years, and the prim has at laft totally difappeared. It is remarkable that thefe difeafes among corn, fruit-trees and fhrubs have generally, if not always, appeared firft on the At- lantic fhore, and gradually extended themfelves into the interior country. This is an obfervation made by many men in different parts of Connecticut. May we not from this circumftance, de- duce an argument, that the infeclion is imported I ! ! IOI But thefe phenomena are not tiew in the world ; they are new only to people who do not read. Aveienna, the Arabian phy-^Avic fician, an author of great celebrity, fays, that " the ftate of air, called corrupt, either impedes the growth of plants or cov- ers them with ruft." Diemerbroeck, de pefte, p. 40. 41, enu- merates, among the effects of a peftilential air, the corruption of grain and fruits, the production of mice and noxious infects which corrode and devour the corn ; the fterility of the earth, which fails to yield the ufual quantity of grain and fruits. He takes notice alfo of another fact, which is, the unufual difpo- fition to putrefaction in all kinds of fifh, flefh and vegetables, during peftilence. This putrefaction, is, by the moderns, confid- ered as a fruitful fource of difeafes. In fome cafes it may be fo ; but it is always an ejffetl of the fame caufe which produces epidemics. Another remarkable fact to prove theuniverfality of the pefti- lential principle, is the ficknefs and death of fifh in rivers and the fea. Several examples are recorded in ancient hiftory. See the years 590, 994, 1240 and others. The number however of fuch facts is not great, in the old books ; and whenever this phenomenon occurred, it was afcribed to froft, to a battle among the fifh, or other improbable caufe. In modern times we have many examples recorded, but prob- ably many others have efcaped obfervation ; or been confidered as things of no moment to mankind ; for within a century paft, the opinion that the plague is propagated, in northern climates, by contagion only, feems to have fufpended all rational enquiries into the caufe of the diforder. That the fifh on the Britifh coaft or in the rivers, perifhed, during the laft great plague in 166^, I find no where related, in a manner to rehder the fact certain ; but I find Hodge has men- tioned a fact of that fort as a proof that peftilence is occafioned by an unwholefome vapor from the earth. The death of the haddock on the coaft of Norway in 1789, has been already mentioned, but as there were many fhocks of earthquake in Scotland, about that period, it is not impoffible that the haddock might have been fuddenly killed by fome concuf- 102 Com of the water. A fimilar event took place on the American coaft, in the great earthquake of November 1755, when fome whales and multitudes of cod were killed, and feen afterwards floating on the water. I throw all fuch cafes out of the queftion, and confine myfelf to the ficknefs and death of fifh, when there has been no concuffion of the waters, to occafion a violent death. The difappearance of the blue-fifh from Nantucket, in 1764, juft after the great mortality among the Indians, is a remarkable fact. Not lefs lingular was the ficknefs and extinction of the Wellflcet oyfters in 1775, the year of a fatal dyfentery in Amer- ica. Still more remarkable was the ficknefs or ill-ftate of the eod-fifh taken on the banks of Newfoundland in the year 1788. They were thin, unfit for ufe and when preferved, turned to a blue or dark color. Ariftotle remarked that no one peftilential difeafe appears to affect all kinds of fifh ; but that thefe animals are fubject to fick- nefs, which is known by their being thin, and not changing then- colors. De Hift. Animal, lib. 8. ca. ao. But to come ftill nearer to the prefent time. In the yeara 1793 and 4, she oyfters on the coaft of Connecticut and Rhode- Ifland, were ail fickly, watery, and taftelefs ; wholly unfit for food, and in fome inftances, brought on naufea or ficknefs in thofe who ate of them. This was the very time when the fcar- latina was fpreading over the country, with malignant dyfentery and typhus. The fhad which came to the New-York market in the fpring of 1796, which was the period of peftilence in New-York, were leaner than ufual, and perifhed, in defiance of the powers of fait. In 1797, multitudes of fmall dead fifh floated down James river in Virginia. It is remarkable that in the fummer following, all the country from Norfolk to Philadelphia, the very latitudes through which that river paffes, was very fickly ; Norfolk, Bal- timore and Philadelphia were all afflicted with the bilious plague. I have been informed, that many dead fhad were feen to float down the Sufquehanna, in June 1798 5 but of the fact, I have not fatisfactory evidence. The reader cannotjfaU to remark here, the correfponden.ee in T03 place between the epidemic difeafes in the water and the air ; the fifh and the human race, in contiguous regions, being difeafed about the fame time—a fact too remarkable to be permitted to ef- cape' particular obfervation. The mortal peftilence among cats, in Europe and America, in 1797, is a fact too well known to be repeated. The fickly ftate of the water in the wells of New-Haven, during the pef- tilential period of 1795 ; was evidenced by the number of ani- malcule it contained. Paracelfus mentions the death of fifh but afcribes it to the influ- ence of the planets. Vol. 1.167. Sorbait relates that in the time of the plague at Vienna, I fup- pofe in 1679, a fountain in the fuburbs, which had been ef- teemed for the falubrity of its waters, exhaled a ftench which appeared to increafe the mortality in the vicinity. Van Swieten Vol. 16. 47. It is probable that Sorbait has miftaken the ef- feet of this ftench ; it is probable the great mortality in the vi- cinity and the impurity of the water proceeded both from one fource, an uncommmon effufion of fubterranean vapor in that particular quarter, or other unknown caufe. All thefe phenomena denote a peftilential caufe in water as well as air. Whether that caufe is a pofitive fubftance infufed in- to the elements from fubterranean regions, increafing the due proportion of oxygen ; whether it is a negative ftate of the ele- ments, occafioned by the abftraction of oxygen ; or whether it is occafioned fimply by a chemical alteration in the elements, by the mechanical operation of the electric fluid, which may pro- duce new properties in air and water, by means of new combina- tions of their parts, are queftions not eafily folved. But with- out attempting to penetrate into the myfteries of nature, and un- fold primary caufes, we may be certain of their effects, andfrorn this branch of knowledge, may deduce ufeful conclufions. We know, for we fee, the effects of fome mortal principle, which, at particular periods, deftroys or impairs the ufual powers of life, through the animal and vegetable kingdoms. We ration- ally conclude that this caufe muft be general, affecting the ele- ments of life, over whole regions of the earth, and beneath the ro4 waters of the ocean. Of fo much we are certain. As to the primary or remote caufes, we fhall probably remain in the dark—• and as to the proximate caufes, we can only indulge a rational foirit of philofophical enquiry, that may lead to probabilities. Sydenham is among the moft refpctable authorities for the doc- trin of a change in the properties of air from a fubterraneous va- por. His words are, vol. i. p. 8. Wallis's Edit. " There are various general conftitutions of years, that owe their origin neither to heat, cold, drynefs nor moifture ; but depend rather on a certain fecret and inexplicable alteration in the bowels of the earth, whence* the air becomes impregnated with fuch kinds of effluvia, as fubject the human body to particular diftempers, fo long as that kind of conftitution prevails, which after a cer- tain courfe of years, declines and gives way to another." The reader will recollect that when the plague firft broke out in Athens, th; people alledged that their enemies had poifoned the wells. In the mortal plague of 1349, the Germans fufpec- ted the Jews had poifoned the wells, and vented their rage upon the harmlefs Ifraelites. Thefe fufpicions doubtlefsarofe from the bad quality of the waters, fimilar to what was obferved in New- Haven in 1795 : And the fufpicion of poifon was full as well founded, as the modern doctrin of importation, in moft cafes of peftilence. The death of fifh in rivers and the ocean, is one of the ftrong- eft arguments to prove the caufe of peftilence to be a fubtle va- por, expelled or exhaled from fubterranean regions. That fifli do in fact die of epidemic difeafes, is a fact as well authentica- ted and as certain, as that epidemic difeafes affect the human race —and it is equally certain that fuch mortality among the fifh, is ufually cotemporary with peftilence among men, on the adja- cent fhores. From thefe facts, we are powerfully inclined to believe, the general caufe which affects the one fpecies of animals, to be the fame which affects the other fpecies. This conclufion is eafy, natural and irrefiitible. What then can be the principle which penetrates the waters, and reaches the animal functions of fifh and oyfters on the bot- tom pf the fea ? Can it be a vitiated ftate of the fuperincumbent io5 atmofphere ? Can a deleterious principle, belonging to the air, find its way through a mafs of water, and deftroy life, as effectu- ally as in its natural fluid, on the furface of the earth ? Thefe are queftions, I pretend not to fulve. But I cannot help thinking that the only efficient caufe, within our narrow comprehenfion, capable of extending the principle of deftruction through the different elements, is the all-pervading energy of fire or electricity. The modus operandi is among the impenetrable arcana of the phyfical world. It may not be ufelefs to introduce here an obfervation made by elderly people in America, that in fickly years, the aurora bo- realis does not appear. It is certain that during the prefent pef- tilential period, fince 1790, that phenomenon has never been obferved, at leaft not in any diftinguiflied degree of brightnefs. But the hiftory of the aurora borealis does not warrant the juftnefs of this obfervation, as a general fact. The years 1564 and 5, which were diftinguiflied by northern lights, were fickly in Europe, and in many parts raged the plague. The fame lights were very fplendid in November 1575, a year when the plague was fpreading over Europe with unufual violence and mortality. The fame were repeatedly obferved in 1580, the year of a moft fevere univerfal catarrh, when the plague raged in Paris, and when Cairo loft 500,000 people by the fame difeafe. Thefe lights were again vifible in 1621, and defcribed by Gaffendus in France, who it is faid gave them the name of aurora borealis. That year was noted for a moft fatal epidemic fmall-pox and the Hungarian fever in Europe ; and the plague which raged among the Indians in America in 1618, had not ceafed in 1621. From this time to the year 1707, we have no account of the appearance of thefe lights. In that year, they appeared, but not of a remarkable brightnefs. If thefe lights appeared in this long interval, from 1621 to 1707, it is ftrange that aftronomers fliould have left us no account of them. Certain it is, that the great Halley never faw this phenomenon till the year 1716, when he was 60 years old, and he began to defpair of ever beholding it. During this long fufpenfion of the aurora borealis, epidemic peftilential difeafes occurred very often in both hemifpheres. V.oL II, Q iorj In the fame interval, thefe lights were never feen in America,; and our anceftors, when they firft beheld them, at the beginning of this century, fuppofed them a new phenomenon in creation.; the memory of them having been loft. In 1719, in November, appeared thefe lights ; which was at the commencement of a fickly period of great feverity and extent —the plague was then raging in the Levant. A fplenchd phe- nomenon of the fame kind was obferved in Feb. 1720, the moft unhealthy year of that period. The fame in the three following years, and in 1725, 1726, 1728, 1730, repeatedly in 1733, a fickly year, repeatedly in 1735 and 36, very fickly years, when the mortal fore throat prevailed—alfo in 1737. From thefe facts, we conclude that the caufe of peftilential. difeafes, has no connection with thefe vifible phenomena of the electrical fluid, as they are obferved indifferently in healthy or fickly years. It is evident however that the lumen boreale»i is, in a certain degree, periodical. Let us attend now to the effects.of a peftilential ftate of ait: and water, in the production of infects and fmall animals. This is one of the moft remarkable fymptoms of a fickly ftate of the elements, and it is the more neceflary to infift on this phenome- non, becaufe it is vifible to every eye, and carries with it, du- ring peftilence, a demonftration of the doctrines for which I contend. In the threfhold of the hiftory of plagues, we meet widi ac- counts of myriads of noxious infects, accompanying thefe ca- lamities. The ten plagues of Egypt are numbered among the miraculous interpofitions of providence, in favor of his chofen people. But fo far as regards moft of thofe plagues, we find, by fubfequent events, they are ufual occurrences during peftilen- tial periods. Such are fwarms of infects called in fcripture flies and lice, and efpecially locufts, which, at this day and in every age, are generated, in unhealthy periods, in fuch numbers as to darken the fun, when on the wing, and which often devour ev- ery fpecies of plants, and even the bark of trees. Thefe ani- mals feem to have their origin in the defarts of Arabia, border- ing on Egypt and Syria ; but they have often overfpread all Pal- eftine, "Judea and Italy—fometimes they have penetrated into ic>7 Germany, Poland and Pvuflia. It is unnecefiary here to enume- rate the inftances related in the foregoing hiftory, of the rava- ges of thefe animals ; the reader has obferved that inftances of their appearance have often occurred in different periods, and that they are always the harbingers or the companions of the plague. This fact leaves no room to queftion, that the fame ftate of air in the oriental regions, which will generate epidemic dif- eafes, will often produce thofe animals in unufual numbers. They do not indeed always attend the plague ; the particular feafon moft favorable to their generation is an exeefnvely dry one; but it is obvious, that they rarely appear in defolating fwarms, except in periods when the neighboring countries are afflicted with mortal epidemics. It is true that, in two or three inftances, hiftory informs us, dreadful plagues have originated from the putrefaction of thefe animals—the inftance of the peftilence on the African coaft, about 126 years before the Chriftian era, is memorable. But while this fact is not difputed, we muft obferve that the fame pe- riod was diftinguiflied for peftilence in other countries, where no fuch local or particular caufe exifled. Great fwarms of locufts therefore in the eaftern countries, may be the caufe of peftilen- tial difeafes, but always by accident ; whereas they are certainly the forerunners or companions of that calamity. See the years 394, 590, 677, 1031, 1084, 1091, n8rj, 1234, 1337, H76, 1646 and 7. Alfo before the Chriftiari era, the locufts of the year 206 and 174. In the deftructive peftilence which almoft extinguifhed the human race, in the reign of the Antonines, about the year 167, the earth was overrun with caterpillars. During a moft mortal period, about the year 590, an inunda- tion deluged Rome, and fuch multitudes of ferpents were brought down the ftream and lodged on the champaign country, as to occafion a great ftench and contribute to the fubfequent mortality. Worms and myriads of flies and other noxious animals are mentioned, in the foregoing hiftory, as the attendants on pefti- lence. See the years 763, 1001,'1106, 1234, 1286, 1348, 1$9°> I575» *5Q8> i6ioandi2. ia8 Lord Bacon informs us that during a plague in his time, theie were found in the ditches and low grounds about London, -a fpecies of animals which he calls toads, with tails two or three inches long—a kind of animals doubtlefs which we often fee in ftagnant waters, but of larger fize. He remarks further, that ," thofe years have been noted for peftilential and unwholefome, wherein there were great numbers of frogs, flies, locufts, &c." Works, vol. 3. p. 166. Ariftotle mentions the multitudes of frogs in fickly years. Prob. fee. 1. Horftius informs us that unufual numbers of frogs, toads, lo- cufts, ferpents, canker-worms, mice, fnails and fimilar infect?, are the infallible figns of a peftilence. To thefe he adds an ex- traordinary abundance of fifh in the fea and in rivers. See p. 253, dc pefte. The commencement of the prefent peftilential ftate in Amer- ica was diftinguiflied by an unufual plenty of fhad, o£. which fourteen thoufand were caught at one draft of a feine, near the harbor of New-York. I have met with one or two writers be- fides Horftius, who have mentioned this phenomenon, among theprefages of peftilence, particularly Paracelfus in vol. 1. 168. The plague of 1635 and 6 in Holland was accompanied or preceded by an incredible number of infects, as gnats, butterflies, beetles, wafps, grafs-hoppers, but efpecially flies, which were fb numerous, as to cover the ceilings of houfes, and even to obfeure the fun in the open air. See Diemerbroeck, de pefte, p. id. In the plague at Laufanne, in 1613, flies were in fimilar abundance. Ibm. The approach of the plague at Dantzick, in 1709, was an- nounced by incredible numbers of fpiders, in the preceding year. Baddam's Memoirs, vol. 6. 13. The year 1633, which produced a peftilential fever among the fettlers at Plymouth in America, was remarkable for fwarms of large flies, which filled the woods with their humming founds. In the month of Auguft, during a dreadful drouth at Bengal in 1770, which cut fhort the rice-crops and produced a terrible famin, and fubfequent epidemic fever, the air was filled with a io9 «loud of infects, of the fize of a horfe-ftinger, with a long red body and large head ; they continued to obfcure the fan for fome days, during which all toads, frogs and infects on the earth dif- appeared, but this cloud in the air did not defcend to the earth. The next year, a million of people perifhed with epidemic difeafes. The prefent peftilential period in America was introduced by fuch multitudes of canker-worms and palmer-worms, as were never before known. Mufquetoes have been the harbingers and attendants on the difeafes in New-York and Philadelphia in 1793, 1795 and 1798. In this latter year, the whole country has been overfpread with grafs-hoppers, which very much injured the meadows, paftures and gardens. On thefe facts I will juft remark, that they ferve to confirm the hiftorical truth of the fcriptures. The whole feries of facts, relative to the great plagues that have afflicted mankind, is a tif- fue of proofs, that the hiftory of the ten plagues of Egypt was written on the fpot, and is a faithful record of facts. If the op- erations of nature are uniform, the fcriptures cannot be a fpuri- ous production. They defcribe Egypt and Syria, as to every thing rcfpecting climate and productions, precifely as they are at this day ; and this fact is alone fuflicient to eftablifh their au- thenticity, againft all the infidels on earth. It may be impoflible to define precifely thofe qualities of air and water which favor the production of unufual multitudes of any particular fort of infects. It has been cuftomary for writers to afcribe them to putrefaclion in the air ; an indefinite and un- intelligible term. It is true that mufquetoes and fome other in- fects are generated in hot, moift, ftagnant air, and in marfhy places, when the putrefaction of vegetable and animal fubftances, is uncommonly rapid. But they are produced in pure water, al- fo, without any apparent mixture of vegetable matter, beyond what is common to all water. Flies, on the contrary, are moft numerous in a hot and dry feafon. Moifture is hoftile to their exiftence ; and in the year 1795, when the rainy feafon commenced about the 20th of July, preceding the fever in New-York, the flies almoft wholly difap- peared, and were fucceeded by mufquetoes. Putrid fubftances 110 are the food of flies, but the feafons moft favorable to putrefac- tion, do not always produce flies in the greateft numbers. In fhort, it is not poffible to account for the myriads of in- fects which appear in particular years, on any known principles of the animal economy, or any vifible properties of air and wa- ter. If unufual numbers of a particular infect appear periodical- ly, as in cafe of the canker-worms, tho I have not fatisfactory evidence of the regularity of their appearance, in uniform peri- ods, we fhould naturally conclude fuch animals to pafs through other forms of exiftence, and to re-appear in a particular noxious form, at the end of definite intervals of time. But were this the fact, it would ftill remain a problem of a moft embarrafling difficulty, to difcover the reafon of their appearance in unhealthy periods only. For fuch is the fact, with moft of the infects, and their tranfmigration, if admitted, will not in the leaft help us to account for their exiftence, in thofe times only when the ftate of the air is unfriendly to human life. But in truth, as to moft of the noxious infects which mark pe- - riods of epidemic difeafes, we know them not to change their forms of exiftence, nor are the times of their appearance, peri- odical. On die other hand, we obferve they appear in fickly pe- riods ; and in unufual numbers, at no other time. We conclude therefore that a ftate of the elements, unfriendly to the health of man, is favorable to the generation of noxious infects, but with- out attempting to explain the particular properties of the elements, which poffefs that prolific power.* All I contend for, by thefe , facts, is, that the peftilential principle, whatever may be its na- ture or properties is a general principle, affecting all the elements of life, and that to this general caufe are we to afcribe the delete- rious difeafes which, at times, fpread over extenfive regions of the earth. Under this juft and philofophical view of the fubject, in- fection finks to a very trifling confideration, among the caufes of epidemic diftempers. The order in which infects and difeafes appear, is not uniform; but it ufually happens that the infects are the firft in order of time. This was the fact in 1770, when the flies clouded the heavens in * May it net be the effect of excitement, owing to unufual electrical ftiraulu*? Ill Bengal, and the worms darkened the earth in America. Such was the fact in 1791 when canker-worms in June gave to our orchards the afpect of winter. But the whole progrefs of epi- demics is more or lefs marked by noxious and troublefome infects. In 1798 and 1799, the meadows in fome parts of Connecti- cut have been almoft covered with fmall toads, of the fize of a chefnut, and as defcribed by Fernelius, " coloris cineritii," of the color of afhes. Thefe animals, in fuch numbers, are unufu- al—they are not of the color of the common toad, and never grow to the fame fize. They come-fuddenly and in a few weeks difappear ! Who knows their origin or their end ? Fernelius numbered them, more than two centuries ago, among the prefa- ges of peftilence, and we are witneffes to the truth of his obfer- vation. If we attend to the ftate of a peftilential air, in refpect to its effects on inanimate objects, we are furnifhed with further proofs, that epidemic difeafes are the production, not of fomites from the fick, but of a general deleterious principle. A remarkable inftance of the corrupt or defective ftate of air, happened in the mortal plague of the year 252. See the defcrip- tion of it under that year. It covered objects with what the hif- torian calls " ros tabidus," a putrid corrupt dew or mould. A ftate of air fo extremely imperfect muft have been utterly infuffs- cient to fupport healthy life, in the animal fyftem. The air of New-York in 1795 produced aftonifhing effects in the generation of mould, and the rapidity in the procefs of pu- trefaction, in flefh and vegetables, was almoft incredible. The fatal angina maligna among cattle in 1682 was attended with a blue mift or dew on the herbage of paftures. See the de- fcription of it under that year. It is not an unfrequent thing that a vifible and offetfuve mift or fog arifes in places, during the rage of peftilential difeafes. . Such a mift arofe and fpread over Dantzick, in Auguft 1709, during th'e plague. This fog was fo thick as to darken the air, for fome time, and had a very offenfive fmell. Baddam's Mem. vol. 6. 14. Schreibner, cited by Van Swieten, Vol. 16. mentions that a finall cloud often liangs over the infected place. It is iuggefted 112 by that able author, that thi contagion, colleded into fuch a ctaud, may be difperfed by winds, and afterwards collect at a different place. It is however more probable, that fuch collections of im- pure vapor, are produced where they exift ; and that, if once difperfed, the particles are not afterwards collected. The phe- nomenon however is no inconfiderable evidence, that a peftilential ftate of the atmofphere, is caufed or increafed by vapors exhaled from the bowels of the earth. In the mortal peftilence at Rome A. U. C. 576, Livy men- tions a bow extended over the temple of Saturn, three mcck- funs, and in the evening following, many tranfient meteors. Lib. 41. 21. A fimilar fog or vapor during eafterly winds, appeared in New-York, in September 1798, in the moft fatal period of the plague. Perfons who felt and faw it, defcribe it as moft difa- greeable to the fenfes ; and its effects were very remarkable. The pavements of the ftreets and other objects were covered with a coat of dew or mould, not however exactly refembling either of thofe fubftances ; not unlike perhaps the " ros tabidus," or " ros fanti fimilis," of the year 252. Its effects were equally wonderful on the leaves of trees, which were covered with fpots, which appeared as if corroded by an acid. And I have feen a cotton garment, which had been waflied, and hung out on the night of the fog, which was alfo covered with fpots of a dark, grey color, and which could not be taken out by any pro- cefs of wafhing. During this period alfo, iron railings and pump-handles were fuddenly covered over with fcales of ruft, or a ferruginous color. Thefe phenomena correfpond with the effects of the peftilential air at Oczakow in 1739, in which fur- gical inftrumcnts became livid or black, as did the filver hilt of a fword. Thefe recent facts which have come un3er my own obferva- tion, have enabled me to give due credit to hiftorians, who men- tion fpots in garments, appearing fuddenly, during the plague. The writers who mention this phenomenon were moftly monks or other ecclefiaftics, whofe relations are highly tinged with fu- peiftition ; and as their imaginations have ufually wrought up thefe anpeatauces into the figure of a crofs, or other chimerical *'3 form, and afcribed to them fome miraculous qualities, I had paffed over the paffages with very flight confideration. I have however tranferibed or rather abridged one of thefe accounts, under the head of plagues in the reign of Juftinian. It is from Warnefred, who relates that in the peftilence at Li- guria, the Genoefe territory, there appeared fuddenly " qusedam fignacula," certain figns or fpots, on doors of houfes, garments and utenfils which could not be waflied out, but grew brighter by waffling. See the account in the foregoing hiftory, under the defcription of the plagues between 542 and 600. I recollect reading feveral other accounts of fimilar phenomena, which, for the reafons juft afligned, I neglected to tranferibe when the au- thors were before me, which I now regret. The celebrated Boyle mentions fimilar phenomena during pef- tilence, and particularly an inftance in Naples in the year 166o, which happened after an eruption of Vefuvius, and which he afcribes to a vapor. The vapor, he remarks, made impreflions of curious figures on garments ; and he cites Thuanus and Kir- cher, as authorities for his opinion. See vol. 5. p. 60. In the dreadful plague of 746, fimilar figures appeared on the garments of people, which the writer calls crucicula?, little crof- fes, which feemed as if drawn in oil. Thefe marks excited no fmall terror, wherever they appeared. Paulus Diaconus, Aug. Hiftory, p. 1012. Similar figures were impreffed on the bodies of the men who were employed by Julian to rebuild Jerufalem in 362 or 3, and who were driven from their work by earthquakes and eruptions of fire. From thefe facts we may be led to afcribe the forma- tion of fuch fpots to fome electrical procefs, or combination with an acid. Thefe phenomena indicate a peculiar ftate of the air, which is not common even during peftilence. It is a ftate which marks the higheft degree of derangement in its ordinary healthful qual- ities, and fuch, as bleffed be God, does not often occur. Another ftrong proof of the doctrin here maintained of a pef- tilential principle in the elements, is the well known fact, that du- ring the plague, fowls abandon the atmofphere of the infected places. Vol. II, p H4 Livy mentions that in the terrible plague in Rome, anno urbis condiue 571, not a vulture was to be feen for two years. Dr. Gottwald remarks that in the Dantzick plague of 1709, fparrows, daws, ftorks and fwallows deferted the place for four months. Dr. Schelwig has recorded a fimilar fact; and Sorbait affirms that birds deferted Vienna during the plague. Thofe kept in cages died. Diemerbroeck has informed us that in the Holland plague of 163 5 and 6birds were unufually rare. He remarks that birds more readily perceive the poifonous ftate of the air, and change their refidence to places more falubrious, even abandoning their nefts and their young. The fame fact has been ©bferved by many med- ical and hiftorical writers. The ancient phyfician and compiler of medical fcience, JEtius, mentions, among the figns of approaching peftilence, the death of birds and quadrupeds. If, fays he, the circumambient air is the caufe of the difeafe, it will firft fhow its effects in deftroying birds ; if vitious exhalations from the earth, are the caufe, quad- rupeds will be firft affected. The fact goes to demonftrate that the peftilential principle per- vades the aerial fluid and is offenfive to the delicate organs of fowls. It may be further mentioned, that the deleterious principle is often fatal to fmall birds in cages, before, it is perceived by the human race. It is a curious and well authenticated fact, that in the prog- refs of a plague, in cities, fmall birds ficken and die ; and not long after, the people in the fame houfe, are feized with the pefti- lence. Diemerbroeck was frequently an eye-witnefs to the fact, and he obferved, that wherever the fmall birds died in cages, the plague never failed, fometime after and often in two or three days, to attack the inhabitants of the dwelling. This is another proof amounting to demonftration, that the peftilential principle is a quality of the atmofphere, and that it is progrejflve in its malig- nity, having little or no dependence on the powers of contagion. See Diem, de pefte, p. 11. After all, the caufe of violent and deftructive epidemic difea- fes may remain a fecret. We fee the caufes of the ordinary dif- eafes of the feafons, in marfhes, ftagnant waters, confined air, and the like j but it often happens that peftilence commits moft "5 cruel ravages, in feafons apparently the moft temperate j and in places evidently the moft falubrious. / The plague in 542, and in fubfequent periods of the fifty years plague of Evagrius, afcended to the tops of the hills and mountains. The terrible plague of 252, in the reign of Gal- lus and Volufian, invaded every village and almoft every houfe. The deadly plague of 1348 penetrated likewife to the moft healthy fpots on the globe and even to the regions of Greenland, fweeping away the human race, with undiftinguifning feverity. Hildanus informs us that in the plague of Laufanne, in 1613, the huts of the peafants on the hills and mountains were not ex- empt from the malady, tho detached and having no intercourfe with the infected. The fame fact is recorded of the plague in 1720, which extended to the villages and mountains of Provence. In the Traite de la pefte, p. 29, it is afferted that in the melancholy plagae at Lyons in 1628, the filthieft houfes, the crouded places, narrow ftreets and confined apartments, were places of the moft fafety ; while the moft airy fituations, as hou- fes on hills, were moft expofed to the ravages of the diforder. No place was exempt—the change of air was ufelefs or perni- cious ; in fome cafes, thofe who enjoyed health in the impure air of the city, on removing into the country, were attacked with the malady. Malouin declares that the moft populous and dirty places in Lyons and Marfeilles were leaft affected with the plague. Thefe facts are very lingular ; yet it is not difficult to account for them, on the principle of a fuperabundance of oxygen, ftim- ulus, or principle of life in the atmofphere. If, as is fuppofed, a ufual caufe of peftilential diforders, is a too great quantity of oxygen in the air, producing firft the ftenic or inflammatory di- athefis, and of courfe indirect debility, then thofe places muft be moft healthy, in fuch a general ftate of the air, where there is the fmalleft proportion of oxygen. This remark however is a mere conjecture ; and the facts related of the plague in Ly- ons ftand as an exception to a very general rule, that the moft filthy, unventilated places fuffer moft feverely by all kinds of peftilential maladies.* * In Lyons, tanners and curriers efcaped the plague, as did thofc n6 It is alfo true in general, that the poor, who inhabit narrow ftreets and alleys, amidft filthy fubftances, fuffer more by malig- nant complaints than the rich, who live in wider ftreets, and more airy, cleanly houfes. To this however hiftory prefents us fome exceptions ; cafes have occurred in which the rich have been the principal fufferers, as in 1361. While it may be difficult to afiign precife reafons for fuch dif- ferences in the operation of the principle of deftruction, the facts prove that this principle confifts in fome hidden qualities of the elements, and does not arife from any of the ordinary vifible caufes of difeafe. Riverius is explicit on this point. He avers that peftilential difeafes often occur, without any apparent change in the vifible qualities of the air, and when the air appears to be more pure than at other times, when no fuch difeafes prevail. Lib. 17. Further, altho it is generally true that peftilence is attended and greatly augmented in violence by fome peculiarity in the fea- fons, as exceflive heat and moifture or drouth, yet to this there are frequent exceptions. The reader may turn back to an in- ftance of this, recorded by Livy and other Latin hiftorians, in which it was remarked as .a matter of furprife, that a violent plague, and one of the moft deftructive kind, fhould aflail the city of Rome, in a mild, temperate feafon. A fimilar obferva- tion was made refpecting the plague in Paris in 1580. The fummer was temperate and the fruits good. No vifible caufe could be afligned for the malady. Yet a moft certain, or rather an infallible fymptom of a deranged ftate of the elements, had occurred in that year ; I mean a moft fevere univerfal influ- enza. Hence it appears, that altho peculiar feafons may prodi- gioufly increafe, and perhaps produce a peftilence ; yet the gen- eral caufe is often fome principle which has no dependence on feafon or changes of weather. In the laft London plague, in 1665, fays Hodge, the feafon was mild, the heat moderate, and fruits abundant, and good. who cleanfed fewers and privies. The fame has generally been the cafe with the fextons, and others employed in burying the dead. See Lan- cifius page 160. In London, fhipwrights who labored in the vapor of tar and pitch, efcaped. J17 ' We have, in America, proofs of the truth of this doctrin* The laft peftilential period commenced with the meafles in 1789 and fevere epidemic influenza in 1789 and 90; and has already continued ten years. Some of the fummers, duringihis period, have been very temperate, as thofe of 1794 and 1797. Yet ev- ery fummer has produced the peftilential fever of our climate ; and even our winters have exhibited fymptoms of the difeafes which prevail in fummer. Not one year, even the moft temper- ate, of the whole period, has failed to fhow the predominant di- athefis of the peftilenee. The fultry dry fummers of 1793 and 98, and the fultry humid fummer of 1795, have rendered the difeafes more violent and fatal in the northern ftates. Yet in the more favorable feafons of 1794, 96 and 97, the morbid caufe produced its effects in New-Haven, Providence, Newburyport and Bofton, as well as in Baltimore, Norfolk and Charlefton. Hence we obferve that the elemental caufe of the difeafes of this period, may be, in fome degree, modified, but not control- led or fubdued by the moft temperate and favorable feafons. Indeed all writers of reputation on this fubject agree, in this one opinion, that the plague cannot be afcribed, either to intem- perate feafons, or to putrefaction, or to any fpecies of exhalations from animal and vegetable fubftances. Thefe are allowed to be fecondary caufes, operating to modify or vary the operation of the primary caufe ; but one uniform feries of obfervations from the beginning of hiftory to this day, has driven medical writers from the defencelefs ground of intemperate weather, and putrid exhalations. Hippocrates learnt that peftilence could not be afcribed folely to vifible caufes ; he therefore admits to the'ton, fomething divine, or beyond human inveftigation, to be a primary caufe of this ca- lamity. Tacitus informs us that the plague in the time of Nero could not be afcribed to any vifible intemperature in the feafons. Fernelius obferves that altho immoderate heat augments the plague and every acute difeafe, yet he had known an exceflively hot feafon, pafs off without producing peftilential difeafes. He u8 agrees with Diemerbroeck, that the caufe muft be fome unknown principle, " inquinamentum e ccelo demiflum," fome caufe of corruption in the atmofphere, which is infufed into it from the ce- leftial regions. This is cutting the gordian knot. Thefe authors are doubtlefs right, in rejecting the vifible qualities of the air, ex- halations and intemperate feafons, a3 the primary caufes of the plague ; but they fly from earth into the boundlefs regions of fpace, for a caufe which is more probably beneath their feet, or around their bodies. Sennertus decides alfo moft pofitively againft putridity or cor- ruption of the humors, as the caufe of peftilence ; and maintains that it proceeds from an occult malignity in the air. Skenkius contends that perfons do not receive the plague from humors in the body, from extraordinary feafons, from inteftine putridity, or corruption of indigefted fubftances, nor from bad food or drink, nor from ftagnant waters, nor from exhalations from dead bodies, cemeteries or fewers, or the fetid waters of tan-yards ; unlefs they inhale the noxious or infecting caufe, e fub- limi. To produce the malady, requires no corruption of the manifeft qualities of the air. Page 764. : Profper Alpinus, who lived fome time in Egypt and had an op^ portunity to make perfonal obfervations on the difeafes of that country, maintains that the plague rarely arifes from corrupt airi and never, unlefs when the Nile has exceeded its ufual limits in its inundations. If, fays this writer, the difeafe proceeded from noxious exhalations from putrid ftagnant waters and marfhes, it would occur every year, which is contrary to fact. Hence he concludes the difeafe to be ufually imported into Egypt from Greece, Syria and Barbary. In this opinion, he has been fol- lowed by a whole tribe of unobferving travellers ; who ftupidly forget that by tracing the diftemper from Egypt to Syria or Bar- bary, they never come nearer to its fource. The queftion ftill occurs, what is its caufe ? where is its fource ? If putrid exha- lations in Egypt will not produce the plague, will fuch exhalations in Syria or Barbary produce it ? Why trace it to thefe countries ? Does any caufe exift in Syria, Greece or Barbary to generate that difeafe, which does not exift in Egypt i TI9 To avoid this dilemma, fome writers infill that its fource is in Conftantinople, where the feeds of it are treafured up in old clothes, and preferved from year to year, and from age to age, But why fuppofe this fource of the difeafe to exift in Conftanti- nople only ? Why not the fame fource forever exift in Egypt, for there alfo infected clothes are never purified. In fhort, from Profper Alpinus to Mead and Cullen, all the reafonings and af- fertions of authors on the origin of the plague, argue either im- potence of mind, want of obfervation or extreme prejudice. So far as this, Alpinus is right, that exhalations alone from ftagnant waters and marfhes willnotordinarilygenerate the plague; but aided by fome general primary caufe in the elements, fuch ex- halations do produce the plague, and in no country more frequent- ly than in Egypt. Gibbon alleges this difeafe to proceed from hot, damp, ftag- nant air, drawing this conclufion probably from the origination of the terrible plague of 542, in the foul regions nearPelufium in Egypt, and in the vicinity of a large marfh. But if this were the only caufe neceflary to produce the diforder, as Alpi- nus juftly obferves, it would occur regularly every year, for every hot feafon generates putrid exhalations in ample abundance, and in every hot climate, will be found annua"! returns of hot, damp, ftagnant air, The caufes therefore afligned by Gibbon are inad- equate to the effect. In America, beyond almoft any other country, we have the moft irrefiftible arguments againft this opinion. No country on earth, not excepting the rice plantations on the river Bengal, pre- fents fuch an immenfe region of ftagnant waters, and fetid marfh- es, as the eaftern fhore of the United States, from the Delaware to Florida. The fouthern extremity of this region is in a cli- mate always warm ; and the whole of it is expofed to burning heat, for four months in the year. Yet the true, " peftis ingui- naria," of the oriental countries has never appeared in this coun- try, as an epidemic ; and the fpecies of the plague which occurs, and which I call bilious or American, appears as rarely amidft the marfhes of Carolina, as in the northern cities, which are expo- pofed to no marfh exhalatipns. 12 O Now if hot, damp, ftagnant air, and putrid exhalations alone were adequate to the production of this bilious plague, it muft be produed every year, in a multitude of places on the American coaft j whereas in fact, that difeafe rarely occurs, as an epidem- ic, even on the flat lands of Carolina and Georgia ; and never is very extenfively mortal, except when the northern ftates, which are fituated on high, rocky, gravelly and dry lands, and whofe air and water are of the moft pure and falubrious kind, are afflic- ted alfo wit'^ malignant epidemic diftempers. This is a remarkable fact and one on which I will venture to reft the whole argument. In no inftance, has the city of Charlefton, fituated on an immenfe flat, furrounded by the marfhes of ,Afhfey and Cooper rivers, been feverely troubled with a contagious bilious epidemic, except when the feafons have been fickly in the northern ftates. Witnefs the years 1699, 1728, 1732, 1739, 1745, 1748, 1796. I fpeak not of fpo- radic cafes among ftrangers that vifit the fouthern ftates, for thefe may occur every year. The Europeans might, had they not been blinded by the falfe notions of contagion, long ago have difcovered the fame import? ant truth; for what is called a great plague in Egypt or Syria, never occurs, except during the prevalence of malignant epi- demics all over Europe, even to the Baltic. Lighter epidemics occur in Egypt and Conftantinople, in any uncommon feafon; and fo does the ordinary autumnal bilious fever, in all our fouth- ern ftates. Thefe are diforders which may be excited, in any place and any feafon, by the action of heat on vegetable fubftan- ces in fhignant water, or by the local impurities which always exift in populous cities. But thefe ordinary difeafes do not put on the malignant fpmptoms which characterize the diftempers of peftilential periods—they do not exhibit infection. On the other hand, when the difeafes of Egypt affume contagious and deadly fymptoms and fpread defolation over that country, we fhall al- ways find the northern parts of Europe, more or lefs afflicted with the fame or ether malignant diforders. The peftilential principle, in greater or lefs degrees of violence, extends over the whole European world, and net unfrequently over the A- merican continent. 121 Thus, altho the plague does not, in modern times, appear in the north of Europe, at leaft not often, yet all the great plagues in the Levant are vifible, if I may indulge the expreflion, in the augmented bills of mortality in London, Amfterdam, and the Baltic cities. Witnefs the peftilential periods of 1720, of 1736 to 1740, of 1760 to 1763. Even the lefs violent peftilences of 1772 and 3, and of 178410 1786,have been marked by epidemics in England and Scotland. And, in the laft feries of epidemics, the years 1792, 93 and 95, which have been diftinguiflied for the plague in the eaft, as well as anginas and plague in America, exhibit a confiderable increafe of mortality in London. All thefe facts ferve as evidence of the truth of what the medical writers of the fifteenth, fixteenth and feventeenth cen- turies have unanimoufly advanced, that the primary caufe of peftilence is fome invifible quality in the elements, altogether diftinct from corrupt air, or marfh exhalations. It is a remark of the Arabian phyficians, that an indifpofition . of the air is neceffary, in the hotteft climates, to enforce the ac- tion of putrid effluvia on the human body to produce the plague. Mead, 248. Dr. Mead himfelf, while he maintains that the putrefaction of animal fubftances, with unfeafonable moiftures, heats and want of winds, produces the plague, and while he contends that no kind of putrefaction in European countries, is ever heightened to a degree capable of producing the true plague, admits that a corrupted ftate of air is neceffary to give the contagious atoms their full force, otherwife the plague could never ceafe, but with the extinction of mankind. That is, he holds the plague never to appear in European northern countries, without contagion, but that the contagion would remain inert, without a corrupt ftate of the atmofphere. The abfurd opinion, that northern climates will not generate the ftate of air which occafions a peftilence, but that a peftilen- tial germ, or leaven, muft be imported from Egypt or other fouthem latitude, has been adopted by moft of the Britifh med- ical writers, and by a numerous part of the phyficians in the Vol. II. Q^ 122 United States. It is hard to fay whether the followers of Mead are the more fervile, or their opinion, the more unphilo- fophical. But for my prefent purpofe, it is fuffkicnt that even the advocates for the propagation of the plague by a fpecific contagion, admit that this caufe is not adequate to the effect, and that they are compelled to fummon to their aid a general princi- ple of corruption in the air, to account for its propagation in northern climates. This conceflion of the exiftence of fuch a principle, by whatever name it may be called, is all I afk. It is on this principle only, we can reconcile the differing ac- counts of authors, in regard to the effect of putrefying bodies after battles, in producing peftilential difeafes ; fome alleging that fuch corrupting bodies will produce the plague, and others denying the fact. Julius Alexandrinus, Diodorus Siculus and other authors, relate that plagues have arifen from the putrefac- tion of dead bodies after battles. Three or four inftances occur in the foregoing hiftory, of plagues afcribed to the putrefaction of dead locufts. Foreftus relates that a dead whale, eaft upon . the fhore of Holland, occafioned an extenfive peftilence in Eg- mont. See Hieronymus, Aguftinus, Sabellicus, Walfius, An- gelus, Parasus, and Agricola, who have recorded fimilar facts, as cited by Diemerbroeck de pefte. Dr. Gottwald relates that the plague which fpread over the north of Europe from 1702 to 17 11, originated near Pickzow, foon after the unfortunate battle between the Saxons and Swedes; but he fays nothing of putrefying bodies, nor does he afcribe the difeafe to that caufe. Baddam's Mem. 6. 5. At the fame time, it it equally true, that thoufands of dead bodies after battles have periftied unburied, without producing any fuch effect. In 1642, eight thoufand dead foldiers and innumerable carcafes of horfes, after a battle in the Duchy of Juliers, were left to putrefy on the furface of the earth, caufing an intolerable ftench, but producing no peftilential difeafe. The fame fact happened often, fays Diemerbroeck, p. 31, in the cruel wars, between the Swedes and Imperialifts, in his days ; and we know that other hiftorians have related fimilar facts. Ill Whenever a malignant difeafe follows fuch an extenfive pu- trefaction, Diemerbroeck alleges, the difeafe to be only a pefti- lential fever, but not the true plague. Or if, in any inftance, the true plague follows, he maintains the putrefaction to be only a fecondary caufe. This is probably a near approach to the truth. The whole myftery is unfolded, on my principles, which teach the exiftence of a difordered or peftilential ftate of the elements, at particular times. If the putrefaction of dead bodies takes place during thefe periods, when the animal func- tions are debilitated, or impaired, and the human body, prone to difeafe, the corruption of flefh may fo far vitiate the atmof- phere as to produce peftilence. But if thoufands of dead bodies putrefy on the earth, when the air is in its natural ftate, falu- brious and adapted to the fupport of health, and when the hu- man body is in full vigor to refift the effects cf the foul effluvia, it is hardly poflible for any quantity of diflblving fltfh to evolve a poifon, adequate to the production of peftilential diforders, and certainly not fufficient to occafion an extenfive epidemic. An attention to this diftinction will alfo reconcile all the differ- ences of opinion, and all the contradiaory phenomena which re- gard the effeas of vegetable effluvia, and the impure air of cities. Why, it has been triumphantly afked by the advocates of im- ported fomites, did not the filthy ftreets and putrefying vegetables of New-York and Philadelphia, produce the bilious peftilence, in former years ? For many years, we recollea, more foul ftreets and docks, much greater accumulations of filth, yet thefe produced not the contagious fever which has lately defolated our cities. Such are the facts, I admit ; and the fame will again take place, when the period of peftilence fhall be clofed, and the la- tent diforders of the elements, correaed. But there has exifted, fince 1789, a univerfal defect in the healthful powers of the ele- ments, clearly evidenced by a feries of fevere epidemics, the in- fluenza and fcarlatina, the increafed violence of the fymptoms of ordinary diftempers; by the imperfeaion of fruits ; by the fick- nefs and death of fifh, fowls and cats, with many diforders a- mong other animals. The moment this ftate of the elements oc- curs, the local impurities which always exift in cities, and which 124 produce only ordinary difeafes, in a healthful difpofition of the elements, give to thofe difeafes new virulence and a contagious quality. The whole fecret to be unfolded, is, that the autum- nal difeafes, under the debilitating operation of a general derange- ment of the elements, acquire unufually fevere fymptoms, a wi- der extenfion, and the quality of contagion or what I call infec- tion. Thefe phenomena excite the aftonifhment of men, who have not attended to the hiftory of peftilence, in which they might have found the means of folving the difficulty ; for fimilar faas have marked the progrefs of peftilential difeafes, from the days of Mofes to this hour. I would further"obferve that from univerfal obfervation, it ap- pears, that during that ftate of air, which produces contagious difeafes in unufual numbers, all kinds of flefh and vegetables are more apt to putrefy, than in a healthy ftate of the atmofphere. This was obferved by Diemerbroeck in the Holland plague of 1636 ; and we have had many proofs of it in America, within a few years paft. And this is evidently true not only of fi efh animal meat, but alfo of faked meats of all kinds. The powers of fait appear to be infufficient to preferve flefh and fifh, againft the ftrong tendency to diffolution, which feems to attend them in certain years. Hence we fo frequently hear of fpoiled beef and pork, and fifh during fickly periods. In feme feafons, it appears to be almoft impofliblc to keep pro- vifions, deftined for a foreign market. This effea on flefh and fifh may proceed either from unufual heat and moifture in the air, orfroman obvious imperfeaionor fickly ftate of the animals ; and perhaps, independent of thefe caufes, it may proceed fometimes from the fame invifible principle in the properties of air, which originates new and malignant fymptoms of difeafe in the human body ; a mere excefs of ftimulus. But whatever may be the caufe, the effea is obvious ; and the unexpeaed putrefaaion of faked meats, has olten been among the caufes which have generated or augmented peftilential diftem- pers in America. Such an inftance is mentioned at New-Haven in 1794, where a quantity of putrid fifli was thrown into the dock, and was exceflively offenfive, juft before the appearance of 12^ the peftilential fever. In New-York, the laft fummer, the peftk fence evidendy received great force and malignancy from large quantities of beef and pork which fpoiled in ftores and cellars. A fimilar caufe is fuppofed to have excited or increafed the fame difeafe in Bofton and New-Londen. The putrefaaion of re- mains of great multitudes of the fifh called Menhaden$ on the wharves in Newburyport, in 1796, was obvioufly a powerful ex- citing caufe of the diforder in that town. In fuch cafes, putreh.aion is more rapid, and its ftench more poifonous, than under a healthful conftitution of the atmofphere. This accelerated diiTolution of flefh is the effeft of the common principle of difeafe, and in its turn, becomes the caufe of difeafe. Hence we may obferve, that it is only during a fickly ftate of the elements, that putrefaaion is ever known to excite peftilen- tial epidemics ; for almoft every man has obferved, many times, that the fame quantities of putrefying flefh, in periods of health, produce no fuch diftempers. It is this circumftance which has puzzled all fuperficial obfcrvers, and furnifhed the advocates of imported infeaion, with ftrong ground to maintain their errors. They allege, " the fame caufes have not always produced the fame effeas. As putrefaaion and filth have not, at other times and always, produced difeafes in our climate, therefore they do not produce the peftilential fever of the prefent time, and it mufl be occafioned by imported fomites." Thefe men have not at- tended to fimilar faas in all other countries and in all ages. The fame argument would prove that no peftilential difeafe can be gen- erated any where ; for it is as true of the Weft-Indies, of E- gypt and Conftantinople, as it is of the United States, that pu- trefaaion does not, every year and at all times, produce pefti- lence. In this fad agree all authors who have written on the caufes of the plague. And there is reafon to believe, with Die- merbroeck, that putrefaaion alone never produces the plague ; but that whenever it is the apparent exciting caufe, there concurs with it a general fickly ftate of the air ; which not being vifible, mankind afcribe the whole effea to putrefaaion. In the United States, it is a very curious faa, that this fick- ly ftate of the elements has been progreflive, as I have par- I2f5 ticularly proved, in the preceding pages, which progreffion was clearly marked by the increafe of mortality by the fcarlatina, and. other difeafes of unufual malignity. In every inftance, the epidemic peftilential fever, tho faid to arife from putrid flefh, has kept pace with this infalubrious ftate of air. For example, while Philadelphia was ravaged by the plague in 1793, the fcarlatina was prevalent in New-York; but the eaftern ftates were exempt, and felt no inconvenience from the peftilential ftate of the air, unlefs in a few fporadic cafes of autumnal fever, of aug- mented violence, which indicated a commencement of the epidemic conftitution. In 1794, this conftitution arrived to its cr'ifls in Conneaicut, moving eaftward in its progrefs ; and at New- Haven appeared the peftilential fever, foon after its precurfor, the fcarlatina. Now whether we fuppofe the. peftilence to be from imported fomes, or from the putrid fifh and clams in the docks, it is remarkable that it did not occur till the ftate of air was evidently fickly, and ill-fitted to fupport life, as appeared by the malignant dyfentery in the vicinity, and by the univerfal prevalence of fcarlatina. This is a curious and important fea. Proceeding eaftward we obferve the fame truth. The pefti- Jeatial fever at New-buryport was faid to be excited by the putrid garbage of fifh—true, but this effea did not take place in 1793, when the fever was laying wafte Philadelphia; nor in 1795, when the fame fever prevailed in New-York. Why ? evidently becaufe the conftitution of air in the eaftern ftates, had not then arrived to its crifis of malignancy. But moving eaftward, the fcailatina began to fhowitfelf there in 1795, and in 1796 was more general and fatal in all the adjacent country. Then follow* ed the peftilential fever, both in Bofton and Newburyport. So that if we admit the difeafe to be of imported origin, or fuppofe it to arife from putrid exhalations, we are ftill compelled to admit the concurrence of fome general caufe in the produaion of the difeafe, becaufe we never know this peftilence to appear, but when other difeafes and phenomena demonftrate the exiftence of fuch a caufe.* In Philadelphia, in New-Haven, and in almoft eve- * If it fhould be faid, that putrid fifli might not have exilted, in other years, in fitwp.tions to expofe the inhabitants : I anfwer, that with- 127 ry place, the peftilential fever has followed clofe upon the heels of that malignant diftemper, the fcarlet fever. With refpea to the duration of this general conftitution of air, we can determin nothing, but by the event. We obferve in hiftory, that fuch peftilential periods are of various length, from three to fifteen years, or perhaps for a longer time ; during which, difeafes are multiplied and augmented ; and all bearing fome peculiar fymptoms, that charaaerize that conftitution or ftate of the elements. On this fubjea the treatife of Sydenham is invaluable. There remains one other view of this fubjea to be confidered in this feaion—this is, the conneaion of peftilential difeafes with famin. Moft authors have remarked that famin is a caufe of pef- tilence, and have cited the old Greek adage, o loimos meta llmon, peftis pofe famem, the plague follows famin. It is a juft remark that the true plague often follows a dearth of provifions ; it is more frequently true, that fcarcity is followed by difeafes of a lefs malignant type. But it is equally true that this order is often inverted, and famin follows peftilence. It is more frequently true that peftilence is neither preceded nor followed by any fcarcity of provifions. Inftances of all thefe fluffs appear in the preceding hiftory. The conclufion is inevitable, that the plague proceeds from fome other caufe, than a deficient or fu- perabundant quantity of food, for it often occurs, independent of either of thefe circumftances. Thus Morellus, de feb. peft. lib. 3, relates an inftance, where no peftilential difeafes fucceeded a fevere famin. Galen men- tions an inftance of a fevere famin which followed as fevere a plague in Rome, yet the famin did not again excite the plague. De Pauw, in his Philofophical Diflertations on the Egyptians and Chinefe, vol. 1. 87, anfwers and refutes the Abbe Four- mont who alleged famin to be the caufe of the plague. " By exad annotations, fays De Pauw, continued during in my obfervation, in numberlefs inftances, immenfe quantities of the entrails of fifh are left to putrefy on the fhores of our rivers, every year, with an intolerable ftench, but without producing the leaft ap- pearance of difeafe. 128 twenty-eight years, we find the plague has raged in Egypt five times, without being preceded by any fcarcity of food, and con- trary to what I once fufpeaed, unreftriaed to a periodical courfe." We know alfo in America, that fcarcity of food can have had no influence in producing the numerous epidemic and peftilential diforders of the laft nine years. On this fubjea Diemerbroeck has a very juft remark, and one that folves all the difficulties that might feem to arife from the differing accounts of the effeas of famin. He fays " Non om- nem, fed illam tantum famem fequitur peftis, qux fames et ipfa a peftilentias caufa originem fumit, (dum ab ea caufa primo fru- ges terrse corrumpuntur, poftea peftis inducitur,) ita ut fames , ilia non fit caufa peftis, fed ipfamet eandem cum pefte caufara . habeat." De pefte, page 3c. " For the plague does not follow every famin ; but that only which arifes from the fame caufe as the plague ; (for by that caufe the fruits of the earth are firft vitiated and afterwards the plague fucceeds) fo that the famin is not the caufe of the plague, 4 but proceeds itfelf from the fame caufe." Whenever there exifts a general caufe in the elements, un- friendly to the health of the human race, and at the fame time, to the growth and perfeaion of grain, peftilence and famin may • be companions of each other ; or they may reciprocally follow each other, according as the general caufe operates firft on ve- getables or on mankind. In fuch cafes, fuperficial obfervers are apt to fuppofe one to be the caufe of the other, when in faa. they are both the offspring of a common caufe. In long fieges, bad food is often a powerful caufe of difeafe, as in the fiege of Marfeilles by Julius Cefar, before Chrift 48. Celar, De bel. civ. lib. 2. 20. In fuch cafes, the bad qualitiesjfil^ of the corn or bread, are not natural defeas in the growth, but '4 the effeas of age, heat, moifture and decay. J Fortunately, the improved ftate of agriculture has rendered a \ dearth of grain, a rare occurrence. In defpotic governments, where induftry of every kind languifhes, and men feldom make provifion for fubfiftence beyond the pafling moment, famin is not uofrequent in modern times, as in Syria after the terriblv fevera 129 winter of 1756-7, when the crops failed, and parents devoured their children, or offered them for fale in market to procure food. But fuch is the ftate of agriculture, in free countries, that crops are lefs liable to fail, than formerly ; and when they fall fhort in a particular country, commerce may ufually fupply the deficiency from fome other climate. A univerfal failure of grain, even under the moft unfavorable difpofition of the elements, muft be a rare phenomenon. Yet with all our improvements in agriculture and commerce, we are not to calculate with certainty that we are never to feel the feourge of famin. There has been, within about a century, a fucceflion of feafons when the earth failed to* yield her accuf- tomed quantity of vegetable food. Such were the laft years of the laft century, when corn was cut fhort by mildew and blaft, not in one country only, but in moft countries. Multitudes per- iftied in the north of Europe, and our forefathers in America obferved, that for a number of years, the very courfe of nature feemed to be altered.. The beginning of the feventeenth century was diftinguiflied by a ftill more extenfive and fevere dearth, which affliaed all Eu- rope, and cut off a large portion of its inhabitants. In the year 1783, the dearth in Scotland was fo fevere that commerce alone faved thoufands from perifhing ; and fo late as the year 1790, our own country experienced a fcarcity that excited univerfal alarm. Both of thefe periods were diftinguiflied for fevere famin in Egypt, Bengal and the Carnatic. Such feas fhow us the all-powerful influence of the invifible energies of nature, and how little avail human efforts, to avoid the fatal confequences of a univerfal failure in their operation. That the principles of vegetation do thus fail, at certain times, pver large portions of the globe, is an unqueftionable truth ; it is equally certain, that fuch events are intimately conneaed with the caufe of peftilence among men. Hence we obferve that men and cattle often perifh with epidemic difeafes, when veget- ables fail to yield their cuftomary fruits. It is not however the want of food which occafions difeafes, fo frequently as the bad quality of it. Next toUe corrupt ftate Vol. II. R *30 of air, fays Riverius, unwholefome aliments are the caufes of peftilent difeafes. Vegetables may acquire unwholefome quali- ties from too much or too little moifture, or from other unknown caufes. Grain of a good quality may alfo degenerate and be- come unwholefome, by heat and moifture, after it is gathered, as in magazines, granaries, or holds of fhips. Such corn may produce difeafes in thofe who feed upon it. But it is doubtful whether mere want of food ever produced a contagious difeafe. Seamen who fuffer and even perifh at fea, in a wholefome air, thro mere hunger, pine away and die with- out difeafe. Whenever contagious diftempers accompany dearth, there is ufually a concurrence of other caufes to produce the effect We may therefore confider the propofition of Diemerbroeck as correa, that famin does not produce the plague, but proceeds from the fame caufe ; yet that fcarcity of food and ftill more certainly, food of a bad quality, may produce difeafes of a lefs malignant type, or very much augment, in violence and extent, the current diforders of a particular feafon. Yet here again our fenfes may deceive us. Corn of an ap- parently bad quality, does not always generate difeafe. A ftri- king inftance of this is related in Sinclair's Scotland, vol. 7. 605. Froft, rain and fnow had turned the corn black ; it was difa- greeable to the tafte ; the ftraw was equally affeaed ; but nei- ther man nor beaft fuffered by feeding on them—fo little do we know of the caufe of difeafes. Intimately conneaed with the fubjea of vegetable nutriment, is the confideration of difeafes among cattle. Whenever grafs is defeaive in wholefome, nutritious qualities, horfes, horn- cattle and flieep are fure to fuffer by mortal diftempers. It is often mentioned in the foregoing pages, and a faa that every man may have obferved, that when contagious difeafes prevail among men, fimilar diforders prevail more or lefs among cattle. Very few of the plagues in ancient Rome, affeaed one fpecies of animals, without fhowing the peftilential principle in others. The fame remark may be made, in all ages, and is true at the prefent period. Sometimes the peltilence invades one foe* ^ ties of animals firft—fometimes another j fometimes the difeafes *p Vill be more general and fevere among men, and fometimes among cattle ; but feldom dtrwe obferve one fpecies of animals feverely affeaed, and the other totally exempt. So far as ,piy% reading and obfervations enable me to judge, difeafes among cattle ufually fucceed exceflive or unfeafonable humidity in the air. The years 1712 and 13, when a plague deftroyed a vaft proportion of the cattle in Italy, and great num- bers in Germany, are noted in England, to have been wet and cold. What was the ftate of the air in the countries where the difeafe was moft fatal, I am not informed. The fhort account I have feen of it, abridged from Ramazzini, in the 6th volume of Baddam's Memoirs, makes no mention of the weather or feafons ; and Lancifius, who has alfo left many particulars re- foeaing it, is not before me. The difeafe however was a true plague, charaaerized with many of the fymptoms of plague in the human body. Authors all agree that the diftemper was prop- agated folely by contagion from a fingle cow, from Dalmatia ; ' and they are fo well contented with this idea, that they tell us little or nothing from which we can colfea the caufe. Like the writers on the caufe of the plague in Egypt, who trace it to Bar- bary or Syria, and there leave the fubjea ; fo Lancifius and Ra- mazzini, tell us the diftemper, which deftroyed moft of the cattle in Italy, came from one cow, in a drove from Dalmatia; and there they flop fhort, without a fyllable to explain why the cow from Dalmatia was feized. All thefe contagion-fticklers refemble the Indian, who, when aflced what the world Hands on, replied, on an elephant—the elephant, on a great turtle, and the turtle, on the ocean. Here he flopped, and as to what fupports the ocean, he leaves us in the dark. The general vifible caufe of peftilential difeafes among cattle, as before remarked, feems to be an excefs of moifture, which renders their food watery and unfubftantial. The fummer of 1751, a year of remarkable mortality among the cattle in Eng- land, was cold and rainy. Such was the feafon in 1348, which was followed by a great lofs of fheep, as well as by peftilence among men. ( Ill Vet all wet feafons do not produce the fame effea ; and we are conftrained to refort, for the caufe, to unfeen properties in the air or the food on which the cattle fubfift.—That the fame general Caufe affeas cattle and the human race, in times pf pefti- lence, is obvious from the analogy of fymptoms in their difeafes. During the prefent fickly period in America, horfes and horned cattle have died, in many parts of the country, with difeafes which are charaaerized with bilious appearances ; in analogy with all the diforders which have affeaed men, during the fame period. Lancifius and Rarnazzini would have treated the fubjea of the difeafe among horfes and cattle in Italy, in 1712 and 13, much more like philofophers and men of found fcience, if, inftead of telling how much mifchief an infeaed cow had done, and how the difeafe had been fpread, by farriers, by dogs and by fliep- hetds, they had defcribed to us the feafons, the ftate of vegeta- tion and the difeafes which prevailed among mankind. They ought at leaft to have conneaed, with the difeafe among cattle, art extenfive plague among men which was then raging in Vienna, Hungary, and other countries, as it had been, for feveral years before, over all the Polifh Jlnd Baltic territories. The frequent prevalence of mortal epidemics among the brutes, is an obvious and irrefiftible proof of fome deleterious principle1 in the elements, which is adequate to the produaion of the worft difeafes, and the deftruaion of life, independent of every arti- ficial caufe. The brutes, if left to themfelves, follow implicitly, a princi- ple of their nature, called inftina. They eat what nature inten- ded for them, and never feed on what is pernicious to their health ; nor will they injure themfelves by eating too much or too little of their ordinary food. Governed by fuch a law, they can be liable to no difeafes, but fuch as muft neceflTarily proceed from : the. air they breathe, the water they drink, or the vegetables they eat, all of which are ordinarily good, nutritious, and well fitted to fupport found health. Their difeafes therefore muft proceed from fome imperfeaion in thefe elements of life, which is occa- fioned by natural caufes. This procefs ©f reafoning appear* to f33 6e ftrialy logical and cdrrea. The conclufions from it are iriev" itabfe. If a ftate of the elements does ever exift, which can* produce difeafes that deftroy the lives of the brutes, without con- tagion or any artificial caufe, we may fafely allege that a ftate of the elements may exift in any latitude which is adequate to the produaion of the moft formidable maladies, that ever affea man- kind. The analogies of the animal economy, and continual obfer- vations forbid us to fuppofe the powers of life in the beafts of the field, tefs perfea, or more eafiiy diflblved, than thofe of the hu- man race. On the contrary, from their following tlieir natural undepraved appetites, in the ufe of food and in all their aaions, their bodies may be fuppofed to be more firm and perfea than thofe of men, who are ufually debilitated by irregularities in living, and other deviations from the laws of nature. If then irrational animals are fubjea to the invafions of mortal epidemic difeafes, which mow them down by thoufands, in defiance of the firm texture of their bodies, and their regular living, a fortiori the human race muft be liable to deftruaion by fimilar means. This reafoning is certainly juft and fubftantial, whatever may be its fate in convincing the reader ; and it proves that the natu- ral operation of fome fecret principle in the elements, is fufficient to account for the moft deftruaive maladies, in every latitude on the globe, without reforting to the tranfportation of fomites from fome one heaven-fcourged country to more favored regions. Dr. Mead and all his fervile admirers who believe him, with- out inveftigating his affertions, allege that putrefaaion never rifes, in England, to a degree that is neceffary to generate a peftilence. But if any man can believe that putrefaaion, as writers are pleaf- ed to call the principle of deftruaion, can rife high enough in the grades of malignity, to produce a plague or contagious mortal diftemper among cattle in England, and at the fame time, never affea the human fpecies, he muft have more pride in the foperem- inent ftation of man in the fcale of being, than I poffefs. The argument from faas is evidently in favor of the theory, which fubjectsall animals, in this refpetf, to the fame laws ; and the 134 analogies of creation will not authorize man to claim the high privilege of exemption from the general laws of the animal econ- omy,—It is an unqueftionable truth, that men as well as brutes, in all latitudes, are often invaded with contagious and deadly dif- eafes, under the operation of the elements, without the leaft ac- ceffion of contagion from fouthern climates or any foreign country. Multitudes of feas warrant this deduaion ; but the progreffion in the violence of epidemic difeafes, the imperfeaion of vegeta- bles, the ficknefs and death of fifh in rivers and the ocean, and of cattle on land, are proofs of the truth of my principle, «Jfich bid defiance to oppofition. 135 SECTION XVI. Of Contagion and Infeclion. X\ O point on the fubjea of difeafes has been more agitated among medical writers, than that of the contagion of the plague, inguinal and bilious. Hippocrates has left no decifive opinion on this queftion, but thofe who maintain the plague not to be contagious, rely on this filence of the father of medicin, as an argument in their favor. Galen's opinion was clearly in favor of the contagioufnefs of certain difeafes. " Quodque periculofa fit converfatio cum labo- rantibus peftilenti morboquum nimirum is non fecus fit contagio- fus, quam feabies aut lippitudo."* p. 379. The author doubt- lefs fpeaks here of other peftilent difeafes, befides the inguinal plague, according to the praaice of the ancients who gave the name of peftilence to other malignant diftempers, when epidemic. His opinion however was that the plague originates in a putridity of the air, inhaled by the breath. " Lues ipfa, ab aeris putre- dine exorta, per infpirationes infiliens, haud unum aut alterum hominem, fed plures quoque civitates depafcit, vaftat, et popula- tur." p. 627. In another pafTage, he remarks, that peftilent difeafes proceed from a ftate of the atmofphere. " Peftilentes morbi a coeli ftatu proficifcantur." This author obferved that peftilential epidemics muft have fome caufe more powerful and extenfive, than contagion, or infeaion. Ariftotle was clearly of opinion that the plague is contagious, and the reafon he afligns why peftilence alone is communicated from perfon to perfon, is, that this is the only difeafe which is * In another tranflation, the latter part of this pafTage ftands thus J " periculum cairn eft, ne concipiatur, ut feabies et lippitudo." j3<5 common to all men. This is not very clear or fatisfaaory ; but he fpeaks of fomites proceeding from the fick, and infeaing others. See Problem, feet, I. Procopius was not a phyfician, but is efteemed as a hiftorian. He alleges that in 543, the mortal plague in Conftantinople was not contagious, and that phyficians and attendants on the fick," did not corttraa the difeafe. On the other hand Thucydides, has declared unequivocally" that the plague in Athens was very contagious. Evagrius alfo has related that the difeafe, in his time, was very contagious, to" particular perfons, while others efcaped, even againft their in- clination. Livy alfo was decidedly in favor of the doarin of * -1 contagion. Petrus Salius Diverfus, cited by Diemerbroeck, was of the * >i opinion, that the plague is fometimes contagious ; at other times, not. Seneca held to the contagious nature of peftilence. So fays Ovid, Metamorph. 7. Quo proprior quifque eft, fervitque fidelius jegro, In partem lethi citius venit. The nearer we approach, and the more faithfully we ferve, the " difeafed, the fooner we fall viaims to the diftemper. Thofe who oppofe the doarin of contagion, not only produce as authority, the filence of Hippocrates, with Avicenna, and other Arabian phyficians, on the fubjea ; but they allege, that if the plague was a contagious difeafe, it would always infect thofe who have communication with the difeafed. But this they aver to be contrary to faa ; and they inftance the efcape of many phyficians, furgeons, grave-diggers, hearfe-men, and others.'' They argue further, that as the breath and effluvia of perfons in ' health, will not expel the poifon of the plague from the difeafed ;:1 fo, on the other hand, the effluvia from the infeaed, ^cannot in, fufe the feeds of the diforder into a healthy body. *'' Gregory Nyffen, a celebrated philofopher and theologian, ' concludes, that thofe who are feized with the plague, after an J intercourfe with the difeafed, contraa it from the fame ftate of"' the air, which occafioned the diftemper in the fick, and not from * the effluvia exhaled from the infeaed body. ' While I cannot * *37 affent to this opinion, in the utmoft latitude, 1 firmly believe it contains a great deal of truth. Diemerbroeck, de pefte p. 44, fuggefts that the ancient phy-' ficians, who paffed over the fubjea of the contagion of the plague, called that quality only contagion, which communicates difeafe by immediate contaa, as in cafe of the itch, leprofy, hy- drophobia and the like; whereas the plague infeas more fre- quently through the medium of the air, vapors, garments and other objeas. Thus the fweat, exhalations, and excrementi- tious matter of the fick corrupt the air, and this infeaed air be- comes the means of difeafe to perfons in health who breathe it. This, fays Diemerbroeck, the ancients did not call contagion, proceeding from the difeafed, but they confidered healthy per- fons taking the diftemper through this medium, as infeaed by the malignity of the air. Almoft all modern phyficians however agree in the opinion that the plague is a contagious difeafe, as Foteftus, Profper Al- pinus, Diemerbroeck, Sydenham, and a multitude of others ; and on this general opinion, have been inftituted quarantine laws and other regulations for preferving cities and countries from the difeafe. Of the value of thefe regulations, we fhall be the bet- ter able to judge, after taking a careful furvey of the queftion relative to the force and effeas of contagion. Within a few years, one author has ventured again to call in queftion the received opinions on this fubjea. Dr. Maclean, in a fmall treatife, has attempted to prove that the pb^ue, dyfen- tery and epidemic fevers are never propagated by contagion. Contagion he defines to be " a fpecific matter generated in a perfon affeaed with difeafe, and capable of communicating that particular difeafe, with or without contaa, to another." This author's general arguments are thefe, That fpecific con- tagion muft neceflarily aa and communicate a difeafe from a fick to a well perfon, within a certain diftance—that in the plague, dyfentery and epidemic fevers, a fmall proportion of people, expofed to the aaion of effluvia from the difeafed, are ever af- feaed by the diftempers, and therefore fuch diforders are not (contagious. He confiders thofe difeafes only as contagious, Vol. II. S i3« which can be received but once by the fame perfon ; as the fmall- pox and meafles. He affirms that the exiftence of contagion in plague, dyfentery and fevers, has been uniformly taken for granted, not only without proof, but even contrary to the evi- dence of numerous and convincing faas. He lays it down as a truth, that all epidemic and peftilential difeafes, which may af. fea a perfon more than once in his life, are caufed by certain ftates or viciflitudes of the atmofphere, producing indireft de- bility. The variety of opinions on this fubjea argues either a want of accurate obfervations among medical men, or of accurate dif- tinaions in terms. The various powers of difeafes to commu- nicate themfelves, either have not been underftood, or they have been imperfealy defined. Let us then attend to faas, the only genuin fource of knowledge. Firft. We obferve that the contagion of the meafles and fmall-pox, takes effea with great certainty, whenever a,perfon in health, who has never been affeaed, approaches fufficiently near to a difeafed perfon. I do not fay it always takes effea; for there are a few exceptions; but thefe are fo rare, as not to impeach the generality of the faa, or principle. The contagion of the plague, dyfentery and violent fevers, does not, under circumftances equally favorable, take effea with the like certainty. On the contrary, a great proportion of per- fons expofed to the effluvia of the fick, entirely efcape the di£ tempers. Secondly. The contagion of fmall-pox and meafles, is not fenfibly affeaed in its operation by heat or colcf, moifture or drouth. It aas with the fame certainty in winter as in fummer, and in every variety of temperature. The contagion of plague, dyfentery and typhus fevers, on th$ other hand, depends almoft entirely on heat for its aaivity, and is fubdued, rendered inert, or totally extinguifhed by cold. Hence an effential difference in the two fpecies of contagion--- that of the fmall-pox and meafles being an effential quality of the difeafes; while that of the other difeafes is an accidental cir- cumftance. *39 Thirdly. The contagion of the plague often difcrimihattl between the natives of particular countries, or men of a partic- ular blood, "or family, feizing one and palling by another, and this through the whole courfe of an epidemic ; but the fmall-pox and meafles make no fuch diftinaions. Fourthly. The contagion of the fmall-pox and meafles is not deftroyed by the purity of the atmofphere ; it aas with the fame certainty on the moft falubrious hills, as in the moft impure re- ceffes of poverty. : Not fo the contagion of the plague, and dyfentery; for as a general rule, thefe difeafes are not propagated in a pure atmof- phere. With refpea to the plague, fome exceptions exift; but it is the ufual faa, that thefe laft named difeafes will not fpread by contagion in a wholefome ftate of the air. By removing the fick, from a city into the country, or otherv/ays placing him in an airy room, and preferving it clean, with all the apparel and utenfils, the contagion is fo diflipated or attenuated, as to be ren- dered harmlefs; the attendants efcape, and the difeafe is extin* guifhed with the death or recovery of the patient. Fifthly. The contagion of the fmall-pox and meafles can never aa but once on the fame perfon. Its firft Operation de- ftroys the capacity of receiving it a fecond time. The excep- tions to this ride are too few to deferve confideration. Totally different is the effea of the plague and dyfentery, for inftead of fortifying the body againft a fecond attack, thefe dif- eafes debilitate the animal powers, and render the patient more fufceptible of the contagion in a fubfequent year. It is admitted by all correa obfervers, that the plague may be received by the fame perfon, times without limits; a perfon in Conftantinople died of the twelfth attack; and many perfons, in the late plagues in America, have been affeaed two or three times. With re- fpea to dyfentery and other contagious fevers, there is no con- troverfy on this point. Sixthly. The contagion of the fmall-pox and meafles, if it takes the leaft effea, produces the difeafe complete. The in- fefted patient may be affeaed more lightly than the infeaing perfon, and the degrees of violence in the fymptoms may be very 146 various; but the difeafe produced, will always be completely formed, and of the fame fpecific type, as that from which it is1 communicated. The contagion of the plague and dyfentery, has not the fame "certainty in its effea. The contagion of the plague very often produces only a naufea and vomiting—fometimes an inferior grade of fever, as an intermitting or remitting fever, of which I havtf myfelf feen examples—very often its effeas are limited to dizzi- nefs in the head, or fevere pains in the glands—and fometimes it has produced external eruptions, without any other material affeaion; as in the celebrated Diemerbroeck, who, in the grievous plague at Nimeguen, was affeaed with a carbuncle on his left hand, while in good health. In 1796, I faw an in- ftance in New-York, in which the infeaion of the peftilential fever had occafioned a lingular fwelling and inflammation in the face of a nurfe, who efcaped the difeafe. Seventhly. We may perhaps add, what Diemerbroeck and other writers confider as effential to give effea to the contagion of the plague, and dyfentery, an apt or fuitable difpofition in the found body to receive the contagion. Some peculiar ftate of a body in health is evidently neceffary to the operation of the infeaing principle of the plague; this is agreed by all authors. But it does not appear that any fuch ftate or difpofition is requi- fite to give effea to the contagion of fmall-pox or meafles, which aas upon all bodies, within the reach of their effluvia. This con- fideration may be the caufe of the firft diftinaion before recited; and a few exceptions exift to the propofition in regard to the fmalKpox and meafles, which, tho rarely, fail of operating on v bodies in health. Thefe are important diftinaions, which, had they been ob- ferved by medical writers, would have prevented the enormous errors of Mead and others, who maintain that the plague is prop- agated, in northern countries, by fpecific contagion only.' The truth is, the plague is a contagious difeafe, like dyfentery, and moft typhus fevers, but the contagion is not fpecific. Specific contagion I define to be, a quality of a difeafe, which, within a fuitable diftance, 'communicates it from a body affeaed 14« with-it, to a found body, with great certainty, and under all circumftances of feafon, weather or fituation. Such is the con* tagion of the fmall-pox and meafles. This contagion is of two kinds ; firft, that which aas by contaa only, as that of the itch, leprofy, hydrophobia and fiphilis ; fecondly, that which produ- ces its effea, with equal certainty, by near approach, as that of fmall-pox and meafles. The contagion of the angina maligna approaches to the fpecific kind ; and if it is true, as fome modern phyficians have aiferted, that perfons can never be affeaed with it, more than once, it comes under the charaaer of a fpecific contagion, but I doubt the faa. Several perfons in Bethlem, were affeaed with the fcarlatina anginofa twice, during the late epidemic ; firft in 1793 and again in 1794. Medical Repofitory, vol. 1. 525. That quality of a difeafe which may or may not excite it in a found body, within a fuitable diftance, or by contaa; and t which depends on heat, foul air, an apt difpofition in the re- ceiving body, or other contingent circumftances, and which may excite the difeafe in the fame perfon more than once, is certainly a very diftina fpecies of contagion, from that of the fmall-pox, and to this I give the denomination of infeclion. With a diftinaion of this fort, which feems to have been firft adopted by an eminent phyfician in New-York, Dr. Bailey, in his treatife on the fever of 1795 page 38, and which is unquef- tionably well founded, we have no difficulty in explaining all the phenomena of contagion, which have given rife to difputes, with- out number and to the moft contradiaory opinions. The plague, glandular and bilious, the dyfentery, typhus fevers, and the milder kinds'of angina, are not fpeclfically contagious, but they are infeclious. They will not and do not propagate themfelves in all fituations, but the operation of the infeaing quality is con- trolled by a multitude of. contingent circumftances. Firft. It is admitted on all hands, that a fuitable and partic- ular conftitution of air, is neceffary to render the plague epidem- ic in northern latitudes. Thus Sydenham fuppofes this difeafe to be conveyed by peftilential particles from one place to another, but not to become epidemic, unlefs favored by the conftitution of 142 air. One ground of his opinion feems to have been a fact rela- ted by Mead, that when the difeafe has raged violently in one town, in the fame climate, a neighboring town has totally efca- ped, by forbiding intercourfe with the infeaed place, as once happened in Tufcany___This faa will be afterwards confidered. Mead alfo, while he declares his opinion that the plague is fpread by fpecific contagion only, like fmall-pox and meafles, and that all plagues are to be traced to Egypt, very inconfiftently ad- mits that a certain corruption of the air is neceffary to give the contagious atoms their full force. Thefe opinions are utterly incongruous ; for if the plague pof- feifes fpecific contagion, like the fmall-pox, then a corrupt ftate of air is not neceffary to give full force to the contagion ; for no fuch ftate of air is requifite to give force to the contagion of the fmall-pox. It fpreads with as much certainty in pure air, as in foul air. Mead's principles therefore overthrow his own theory*' But he was driven to admit fome general conftitution of air, to ■ be neceffary to the propagation of the plague, becaufe he had learnt from reading that the plague will not fpread in all places, at all times and under all circumftances. In truth, Mead never had an idea of the difference between the fpecies of contagion ; and the fame may be faid of moft modern writers.* * It is a moft extraordinary circumftance that the Britifh authors, in modern days, mould all agree that a favorable conftitution of air is ne- ceffary to propagate the plague, and yet that no plague is bred in north- . ern climates. They muft admit and do admit, that fuch a favorable ftate of air has often exifted in all parts of Europe ; this is a kind of 1 half way bufinefs ; allowing northern climates the power of creating and preparing a condition of atmofphere that fhall meet the plague half-way. But will it be denied that the petechial fever and angina maligna originate in northern latitudes ? I prefume not. Then the condition of air is admitted to produce moft deadly infeSiout difeafes, but not the moft deadly of all. Kind heaven, in mercy to the northern world, has permitted the elements to generate difeafes almoft as bad as the plague, but not quite. I then afk, does not the production of the angina maligna fuppofe as deleterious a principle in the air, as that of the plague ? Is not the difeafe as fatal to youth, and more certainly infectious or contagious ? This cannot be denied. That difeafe fometimes deftroys as great a pro- • portion of patients feized as the plague, and is more certainly conta- gious to youth ? Befides this diftemper depends not on local caufes, but wholly on a condition of the elements; it therefore implies a molt eiTen- tial alteration in the atmofphere. »43 Sanaorious, cited by Van Swieten, remarked that the rayi of the plague may be removed by the wind, yet he was furprifed to obferve that thefe rays from the body of a difeafed perfon, are never difturbed by the force of the air. I do not perfealy reconcile thefe remarks ; but it is an indubitable faa, that a, peftilential ftate of air, when clearly and diftinaly formed in a city, is not diflipa- ted, nor very greatly affeaed by the moft violent winds. It has fometimes been remarked, that the peftilential fever in American cities, has been fpread by particular winds ; but it has fpread not only before, but againft the wind, tho perhaps with lefs rapidity. Certain it is, that no force of wind whatever ever expels from a town, or leffens the peftilential virus without the aid of other eaufes. Of this we have had repeated proofs in America. Perhaps we may explain this faa, and reconcile the obferva* tions of Sanaorius, on the principle I have unfolded ; by fup- po fing the effluvia of the fick to be, in fome degree, capable of diflipation by the wind, which is undoubtedly true ; but that the elemental caufe of peftilence, which confifts in the effential prop- erties of the atmofphere, is not fubjea to difperfion or removal by the winds. This confideration would involve a curious quef- tion, viz. whether, in the apparent motion of air, called wind, the whole mafs of the furrounding atmofphere is moved, or whether it is the vapor, or other component parts of the air only, which are moved, while the fire or dearie fluid remains ftation- ary. But whatever may be the caufe, the faa is certain, that the peftilential principle, during a plague in a city or town, is never expelled by winds. A moft violent, cool north-weft wind fwept the city of New-York, on the 19th and 20th of September 1795, without any confiderable abatement of the peftilential fever. This faft adds no fmall weight to my opinion, that the primary caufe Further, if petechial fever is generated in northern climates, it de- monftrates the power of thofe climates to produce the plague ; for it has been proved, that this fever is the fame fpecies of difeafe, and otV tens turns to the plague. It has done this, very often in England and on the Baltic. Infection fpreads certain difea£es,and ought to be avoided ; but med- ical men have afcribed ten times more effects to that caufe, than it ever produced. The fame principle which generates the angina maligna or plague, in one inftance, muft be competent to produce it in all othee perfons of like difpofition and habits. 144 of fuch difeafes, is in the effential combination of the component parts of the atmofphere,* Sanaorius further obferves that " things infeaed with the plague, communicate the difeafe, as long as the proximate and remote caufes fubfift ; one of which ceafing, the infeaion ceafes." This is an explicit acknowledgment that the contagion is not fpecific, but dependent on fome other caufe, agreeable to the doarin of Sydenham. This principle is verified moft remarkably in Egypt, as appears by all the authors who have written on the fubjea. They are all conftrained to admit, even when they allege the plague to be not native in that country, that, if imported at certain feafons of the year, it will not fpread. Profper Alpinus exprefsly de- clares that the plague is never imported in the months of June,\ July and Auguft ; " nunquam vifa eft peftis illuc ex infeais lo- cis profeaa ;" altho he maintains that the difeafe is almoft al- ways imported. This is certainly a moft extraordinary aflertion, and unworthy of the reputation of the writer. What in the name of fenfe and confiftency, fhould prevent the feeds of fuch a difeafe from be- ing " imported" in a particular feafon, when veffels are palling continually between that country and infeaed places ? The idea betrays extreme weaknefs or prejudice. Savary in his letters on Egypt has detailed the true ftate of faas. He faw veffels, which arrived in Egypt from Turkey, in the month of Auguft, and landed their infeaed goods and peo- ple, without communicating the difeafe. He informs us, that it is an obfervation of ages, that infeaed merchandize brot into ( Egypt, in the months of June, July and Auguft, do not excite the plague, but the difeafe expires of itfelf. If introduced at * Warm foutherly rains however high the wind, ufually increafe the violence of the difeafe, by inducing debility and giving activity to the local caufes, as noxious effluvia from vegetable fubftances. Cool north- erly winds, accompanied with heavy nins, leffen the morbid action of the peftilential principle ; and if late in the feafon, and not fucceeded by j very warm weather, may entirely remove it. A violent tornado, with great rain, on the 8th of October 1797, was fuppofed to put a ftop to the peftilential fever in Providence. Water decompofes the poi- . fon, or incorporates it into its own mafs—but beat after moifture occa- f;ons a more rapid decompofition of vegetables and increafes the poifon. '45 other feafods, and communicated, it ceafes ; but if imported in winter, it fpreads. The author has here ftated effeas or phenomena, with a good degree of accuracy ; but has entirely miftaken the caufe. It is wholly the ftate of air, in different feafons, and not infeaion, which occafions thefe varieties. Mackenzie, in an account of the plague in Conftantinople, tho a firm believer in its contagion, declares " that both in that city and in Smyrna, the plague breaks out in fome years, when it is not poflible to trace whence it is conveyed." This is doubtlefs true ; yet neither this faa, nor the known fea that contagion in Egypt will not operate in a certain feafon of the year, has ever opened the eyes of European authors to the ab- furdity of the current notions about the fpecific contagion of the difeafe. A faa related by Patrick Ruffel, in his hiftory of the plague at Aleppo in 1760, is full to the fame point, that the contagion of trie plague, will not take effea, without the aid of other caufes. In 1759, the difeafe was inuoduced into Leinfol, a poitonthe fouth fide of Cyprus, where it fpread. Larnica, a town forty miles diftant, received part of the infeaed crew, which brot the contagion to Leinfol. A conftant communica- tion was held between the two cities ; peafants and mule drivers entered Larnica, with their peftilential fores upon them, and were daily in the ftreets and markets. Some died in the houfes of the inhabitants. Other veffels alfo arrived with infeaed crews from Egypt, fome of whom died on landing. Yet mark the iflue—all this contagion did not excite the plague in Larnica! But in the beginning of the next year, eight months after, #e difeafe appeared in Larnica, without contagion, and made great havoc. See Ruffel, page 4. * This faa and others compelled the author to admit that the difeafe is not always contagious, and that it does not become epi- demic, without a certain ftate of air. See pages 4, 5, 7, 1.7, 19, 307.. Thefe faas are of infinite confequence in direaing the application of laws of quarantine ; a fubjea to be hereafter difcuffed. Vol. II. T 146 Innumerable examples may be produced of plagufc appearing in a few detached cafes, without becoming epidemic and with- out extending itfelf by contagion beyond a fingle family. Often it appears in fporadic cafes, without exhibiting any contagion. Follinus relates an inftance of a family, in which the father, mother, with two children and a fervant died of the plague, without glandular fwellings, and without fpreading the difeafe be- yond that family. Joubert informs us of an inftance in 1574, of a refpeaablc family, which loft ^half of its members, by the plague^ which ceafed without fpreading the infeaion. This was at the com- mencement of a moft peftilential period. Matthias Untzerus relates, that at Halle in Saxony, he was an eye-witnefs of inftances, in which here and there a family had been feized with the plague, introduced from other places, without any ill effeas in the reft of the city—the difeafe termi- nating in thefe families. Diemerbroeck obferved fimilar faas. In Oa. 1661, the daughter of a noble widow, was feized with a violent difeafe re- fembling the plague, in the midft of a town where no plague exift- ed,and no foreign caufe could be afligned for the difeafe. The fer- vant, who attended her, died, and the infeaion extended to feven perfons, in fucceflion ; the reft faved themfelves by flight. Thefe perfons died, without the glandular tumors, and of courfe fome of the attending phyficians, denied the difeafe to be the plague. Diemerbroeck, on the contrary, judging from all the fymptornSj pronounced it the plague. It happened that one of the maid* fervants, who left the family and was going to her brother's at Amfterdam, was infeaed and feized with the plague, which foon put on the genuin marks of the difeafe, in an inguinal tumor and two anthraces. She recovered, but infeaed two of her broth* er's children, and there the difeafe difappeared* No local caufe could be afligned for the difeafe in that family. The plague was not before in the city or country, the houfe was a fplendid, ele- gant one and kept remarkably clean, remote from any filthy place, and had never been known to have an infeaed perfon in it. Hence our author concludes very juftly that a peftilent dik *47 eafe is notalways epidemic, nor is an epidemic always danger- ous, nor i« peftilence neceflTarily common to many people ; but that the fpreading of a difeafe by contagion, is wholly an acci- dental circumtlance. See p. 13, 14, of Diemerbroeck de pefte. On this laft faa, I will only obferve, that the year it hap- pened, was 1661, the beginning of the conftitution which pro- duced the augmented violence of the difeafes of London, as re- lated by Sydenham, and the conftitution which occafioned the plague in Holland in 1663 and 4, and that in London in 1665; It is to be regretted that thofe able phyficians and accurate ob- fervers had not extended their views of the fubjea to a prevaU ence of that peftilential conftitution, in various countries, at one and the fame time, inftead of reftriaing their obfervations, each to his own country. The author of the Traite de la pefte, who was a warm ftick- ler for the origin of the plague at Marfeilles in 1720 from im- portation, and wrote a treatifeto prove it, has however demon- ftrated the contrary. He has admitted that the air of Marfeilles was peftilential and produced difeafes marked with buboes and carbuncles, in the autumn preceding its fuppofed importation. But this is not all ; he has recorded faas which confirm all that has been cited from Alpinus, Savary, Ruffel and others, that the contagion of the plague will not fpread the difeafe in an atmof- phere not favorable to its propagation. He informs us, that the difeafe fpread from Marfeilles, in fpite of all precautions, and infeaed more than fifty villages of Provence. This was afcribed to infeaed goods conveyed from Marfeilles. Yet the furround- ing provinces of Languedoc, Velais, Dauphine and others, which he acknowledges to have been inundated with goods from the fame city, efcaped all infeaion. In Provence, the diftem- per reached the inhabitants of mountains and was not even ar- retted by the rigors of winter ; while in the adjoining territories, no perfon was affeaed, tho equally expofed to infeaion. The author remarks further, that the difeafe paffed over fome villages, and infeaed others beyond them ; for which no reafon could be wfligned, while all were alike expofed. 148 Thefe faas were very furprifing and unaccountable to the au- thor, Chieoyneau ; yet there is no difficulty in explaining them, on the principle for which I contend ; that the propagation of the difeafe depends entirely on a favorable ftate of the atmofphere, and not the leaft on contagion. Almoft all the fuppofed inftances of infeaion from merchan- dize, related in authors, when inveftigated, are found to be mere fuppofitions and conjeaures, raifed and fpread by vulgar credulity, without the leaft foundation, and afterwards recorded as faas, by medical writers, who are infinitely lefs excufi-ble, than other people. I have inveftigated many fuch inftances in America, where reports had become popular, and grown into fuch credit, as to be generally believed and received as fafts, and I have, in every cafe, found evidence amounting to demon- ftration, that thofe reports were idle furmifes, very often puerile in their origin, and utterly unfupported by faas. Some of the received opinions, in regard to the imported infeaion of plagues in Europe, when fubjeaed to careful fcrutiny, prove to be equal- ly deftitute of foundation. Among thefe, are the opinions, re- ceived and recorded by grave writers, relative to the London plague of 1665, and that at Marfeilles in 1720. The fuppofition that the plague was conveyed from Marfeilles into fifty villages of Provence, by means of merchandize, ap- pears to be no better founded. Setting afide the errors would produce fever in every per- > Ton ; and for the fame reafon, all perfons alike would be feized with peftilence, during the reign of the dog-ftar. De dif. feb. cap. 4. In conformity to thefe ideas, Diemerbroeck, p. 50, lays it down as a principle, that no perfon will receive infeaion, unlefs his body has an aptitudinem, a fitnefs, or difpofition to receive it, arifing from fome fecret quality or bad ftate of the fyftem. On this point, we reafon without knowing caufes ; all we can do is to colfea and arrange feas, which decide in favor of this hypothefis. We are compelled to admit the principle, not « only as it refpeas the operation of infeaion, but alfo of the ele- mental or primary atmofpheric caufe of peftilence, which makes an evident diftinaion, at times, between perfons of different habits, families, and nations.* * Medical men are not agreed, as to the. nature of what is called/nr- difpoftion. Brown, in Elements of Medicin, defines it to be a lefs degree of the difeafe ; that is, the commencement of the difeafe. I fufpect this definition, properly limited,- to be nearly juft. It is probable that all fevers are the effects of debility, and that when this debility com- mences, a perfon may be faid to bepredifpofed to difeafe ,• altho the difeafe may Hot be formed in many days or weeks after, or may be prevented . by early applications. 159 Thefe faas came under the obfervation of Procopius and Eva- grius. In 543,fays the former, no phyfician or attendant caughfr the diftemper—while many were feized they knew not from what caufe and fuddenly died. Many, fays Evagrius, who fled from infeaed places, remained fafe themfelves, while they communi- cated the difeafe to others. Many who remained with the fick and freely handled them, wholly efcaped. - Others, in defpairfor the lofs of friends, threw themfelves in the way of infeaion, but were not able to contraa the difeafe ; while others received the difeafe by the flighteft conneaion with infeaed houfes, or in open market. We have many memorable examples of a fimilar nature in A- merica—they are too numerous to be fpecified. I fufpea how- ever that four fifths of fuch cafes are improperly afcribed to infec- tion. Diemerbroeck relates that in the height of the plague at Nimeguen, the air was fo bad, that all places were nearly a* like, as to the danger of infeaion ; perfons received the difeafe with or without intercourfe with the fick. Sometimes the plague difcriminates between natives of differ- ent countries. The French fugitives from the Weft-Indies, who have refided in our cities during peftilence have generally efcaped. This is not however very remarkable ; as they are accuftomed to a climate which is, like our fummers, peculiarly fitted to pro- duce a fimilar difeafe ;. at the fame time, their manner of living is better fuited to the warm feafon, than that of our own citizens. But a. fimilar difcrimination has been often obferved, among natives of the fame latitudes, or nearly the fame. Thus Carda- nus, lib. 8, relates that in a peftilence at Bafle, the Swifs only were affeaed ; the French, Italians and Germans.efcaped. John Utenhovius relates that in a plague in Denmark, all ftrangers, as Englifh, Germans and Hollanders efcaped, altho they refided in families and aflbciated freely with the infeaed. The Sudor Anglicus, when it firft appeared in England, attacked none but the Englifh ; but in fubfequent peftilential conftitutions, it inva- ded almoft all Europe. We have in America moft illuftrious examples of the diftinc- tion above mentioned. In the fweeping peftilence of 1618, when i6o almoft all the Indians perifhed, on a traa of three hundred miles. in extent, Tome white men wintered in the country and aflbciated freely with the fick, without injury. In a fimilar peftilence a- mong the Indians on Nantucket, in 1763, not a white man was affeaed, tho never fo much expofed to infeaion. Two or three other inftances have come to my knowledge. A like difcrimi- nation took place in Egypt in the time of Mofes. Sometimes the plague tingles out particular families. Thus Diemerbroeck obferved in the plague at Nimeguen, whole fami- lies, by a fecret fympathy, were feized all at one time ; and in fome inftances, where the members of the fame family lived, at a diftance from each other, in different parts of the city, they were all attacked nearly at the fame time. What is more remark- able, the fame fact^was repeatedly obferved, where the members of the fame family lived in different towns. Of this there were many exemples. One man by the name of Van Dans, to pre- ferve his children from infeaion, fent two of them to Gorcum in Holland, to refide with his friends, and kept the third at home. There was no peftilential difeafe in Gorcum, at that time, and the" two children remained in health for two or three months ; but at laft both were feizedjvith the plague and died, at the fame time that the father and another child died with it in Nimeguen. The mother was feized, but recovered. About the fame time, a filler, and two or three other children, refiding with another fifter, at a diftance, and feveral more remote relations of the fam- ily, all perifhed with the fame difeafe. So it is 'related by Evagrius, who was furprifed at the faa, that particular families, fometimes only one or two, were arref- ted by the plague, while all the other inhabitants of the city re- mained in health. But he remarks further, that thofe who efca- ped, the firft year, experienced the like calamity in the next. This faa, by the way, is common, and fhould have led Evagri- us and others to obferve the progreflivenefs of the peftilential caufe. Pliny, lib. 7. ca. 50, remarks that old people are ufually ex- empt from attacks of the plague ; but that all nations are fubjea to peftilential difeafes, which invade them by kinds or claffes, i6i fometimes falling on fervants, fometimes on nobles, and on oth- ers by grades or ranks. Nature, fays this author, has even pre- ferred certain laws to difeafes. The laft remark thould have excited the minds of phyficians to difcover thefe laws. Such laws certainly exift, and epidemics of all kinds are conneaed in principle. I have met with other inftances of difcrimination, perhaps more remarkable. One is related from John Helwigius, in Bo- netus' Colkaion of Northern Medicine, page 228. In 1621, when the fmall-pox raged with great mortality, it was remarked that perfons of the fame blood, as brothers, coufins and other relatives, living at a great diftance from each other, and as far as from Nuremberg to Lyons in France, were feized with the difeafe at one and the fame time. I draw no important confer quences from this faa, becaufe this difeafe is not limited to par- ticular families, altho it may feize one family before it does another. Another inftance is related by Van Swieten, VoL 16, from Heifter, an author of undoubted credit. At Altdorf, in Fran- conia, broke out in 1711, a malignant fever, approaching to the plague in violence, but not with the glandular tumors. This; difeafe attacked none, but the ftudents or others of the univerfity ; but it feized them wherever they were difperfed in private fami- lies, in all parts of the town. It feized the profeffors alfo and their families, but went no farther by infeaion. It attacked alfo the printer to the univerfity and his workmen, tho at a diftance from the college ; while another printer, contiguous to the col- lege, efcaped. Students alfo belonging to the univerfity, tho at home, as at Nuremburg, were feized. It was thus reftriaed in its attacks, and exhibited no infeaion, beyond thefe defcriptions of perfons. It muft not be omitted, that this was a very fickby period in all the north of Europe. In this fame year, the plague raged in Copenhagen, and it had in the preceding years, fpread over Po- land and along the Baltic. This faa at Altdorf is by far the moft lingular, that I have found in hiftory ; but that a violent difeafe thould attack perfon? of one blood, and not of another, is lefs furprizing. We have Vol. II. W 162 recent proofs of this difcrimination in America. In 1796, three perfons of one name in Hartford, two brothers and a coufin, were fuddenly feized with a violent fever, of a putrid tendency, tho in winter, and carried off within a few days of each other. At the fame time, two or three others of the family were feized lefs violently in the fame town and recovered ; and what is more lingular, two other brothers, one in Litchfield, 30 miles from Hartford, and another in New-York, 130 miles diftant, were attacked nearly at the fame time, and were very ill, but furvived. No infeaion could have exifted in moft of thefe cafes, as the per- fons did not fee each other.* Another inftance occurred in Cambridge, Maffachufetts, and is ftated to me by the attending phyfician. In Oaober 1791, a young woman, belonging to a family in that town, but who had, for two years, lived at a diftance of three miles from her father's houfe, was feized with a putrid bil- ious fever. Her mother repaired to the place and nurfed her, till the was convalefcent. None of the family vifited her while fick, except the father occafionally, and her eldeft fifter. The latter took the place of the mother, for a few days, who was called home to attend two other children who were feized with the fame difeafe, and who had never been expofed to infeaion. Before thefe recovered, three others were taken with the fever in the fame family. The three laft had doubtlefs aflifted in nurf- ing the fick or been into their rooms, and therefore might have been infeaed. In April following, another of the children, who had lived at a diftance from the family and had not been permitted to fee any of the fick, was feized with the fame fever, at the houfe where the lived. In the fame month, the father and another child, were taken with it at home. Not one of the family, at * A curious fact is related to me by Dr. Dutton of Oxford, in Der- by. In the year 179J, almoft every male child, born in the beginning of the year, in that and the adjacent towns, died within a fortnight by convulfions, but no female child was affected. This was obferved to be more frequent in families that had been affeaed by the fcarlatina, in the preceding year. It will be remarked that this was near the diftrict of country which had fuffered by a peflilential fever and dyfentery. home or abroad, efcaped, except the mother, who had nurfed all the fick,except one, and was moft expofed to infeaion. The difeafed were very offenfive, but all recovered, except one; and neither my informant, the attending phyfician, nor any nurfe or vifitor, out of the family, was in the leaft injured by infeaion. M. S. letter from Dr. Wm. Garaage. . This difeafe was a family peftilence, which began in autumn, was fufpended by the cold of winter, and revived in fpring. It refembles, on a fmall fcale, the great plagues in London and 0 Marfeilles, and many others, in which a few cafes occurred, in the preceding autumn, clearly marking a peftilential ftate of air, in that particular city, which ftate was arretted in its operation by cold in winter, but again exhibited its effeas in fpring. The limitation of the difeafe to a particular family, of the fame blood, or difpofition to be affeaed by a certain morbid ftate of air, is a myfterious phenomenon, but the faa is fo well as- certained, as to leave no room to queftion its exiftence. We can afcribe it only to a general ftate of air, fitted to produce injuri- ous or fatal effeas on bodies of a particular temperament, which temperament or difpofition confifts in the invifible ftruaure or organization. It is demonftrated that infeaion cannot beTthe only caufe of the difeafes in thefe families ; and of courfe we are compelled to admit the exiftence of another caufe1, which can only be the atmofphere, for no other caufe extends its operation to the diftance at which the effeas were produced. It is on this principle alone that particular perfons or families efcape the worft plagues that have afniaed mankind, as related by Evagrius, and all authors on the fobjea, and of which we have numerous inftances in America. But, " Why drew Marfeilles' good bifhop purer breath, When nature fickened and each gale was death ?" is the interrogatory of an inimitable poet, which has never been anfwered ; for on thi$ fubjea, as on every other, we are baffled and confounded, when we attempt to reach primary natural cau- fes. The interior organization of animals and vegetables, is far beyond the limits of human inveftigateon* tfj4 Lord Verac'iam has left a paffage confirmatory of the foregoing principles. " The plague, fays this great obferver of faas, is not eafily received by thofe that continually attend the fick, as phyficians; nor again by old people, and fuch as are of a dry, cold complexion. On the other hand, the plague fooneft feizes thofe that come out of frefh air, thofe that are falling and chil- dren. It is alfo noted to go in a blood, more than from ftran- ger to ftrangen" Works, Vol. 3. It is in analogy with the foregoing feas, that animals of differ- ent fpecies are affeaed with epidemic difeafes, which bear a fi- militude in their predominant fymptoms, at different ftages of a peftilential conftitution of air. Sometimes, horfes, cattle and fheep feel the operation of the deftruaive principle, at the fame time with man. At other times, this principle will affea cattle a year before it reaches mankind. Sometimes, it firft aflails the human race, and afterwards the irrational parts of creation. In fome years one fpecies of animals is affeaed ; the next year, a- nother. Thus horfes experienced the epidemic of 1793, in the vicinity of Philadelphia, in the winter following the plague in that city. The cats perifhed in 1797. The fifh in James' river died in 1797, the oyfters on the foores of Conneaicut fickened in 1794, and tie fowls in Conneaicut in 1796. Not unfrequently, the force of the peftilential principle, in one tountry, feems to expend itfelf principally on the brute creation ; While, in the fame year, or fucceflion of years, its principal ope- ration, in a neighboring country, is experienced by mankind. Thus in 1712 and 13, a very peftilential period, the cattle in Italy, Germany and other places received the full force of the peftilence, in a defolating epidemic, while in Auftria, Hungary and the eaft, the peftilence fell on men. Thus alfo in 1770, while a dreadful plague was raging in Turkey and Poland, a mor- tal, diftemper fwept away the cattle in Holland, Flanders and fome parts of England, and malignant fevers prevailed in fome parts of America. That the great general caufe of the difeafes, among the differ- ent fpecies of .animals, is the fame, is obvious from this confid* eration, that during the fame conftitution of air, or peftilential i65 period, the difeafes of man and beaft have a number of fimiljtf fymptoms; fuch was the faa in Auftria, Italy and Germany in 1712 and 13 ; and fuch has been the cafe in the United Statea In conformity with the general principle above mentioned, we obferve that however analogous may be the fymptoms of difeafes in man and beaft, the drftempers of one rarely infea the othefc. Infeaion is limited ufually to that fpecies of animals, which have an aptnefs to receive the operation of the primary atmofpheric caufe of the difeafe. Thus difeafed horfes do not infea men, nor difeafed men, horfes. So when a plague attacks the natives of a particular country only, the infeaion, like the primary caufe ' Of the difeafe, is reftriaed in its operation to thofe particular peo- ple. But this is rarely or never the cafe with the fpecific conta- gion of the fmall-pox and meafles, in regard to mankind; Authors indeed relate that hogs, dogs and poultry, feeding on highly infeaed articles, or wallowing in the filth thrown from houfes, during the plague, have died with a fimilar difeafe. A few inftances are mentioned by Diemerbroeck, Boccace and others. Hodges mentions a difeafe taken from a horfe, which ceafed without becoming epidemic. But thefe ifolated faas form no exception to the general rule j for fuch diftempers never fpread and become epidemic. They only prove my general doarin, that the contagious quality of plague, is not a fpecific principle, but a quality capable of every pofnble degree of force—that in its lower or more attenuated forms, it affeas few or no perfons whatever ; but it may be fo concentrated or condenfed, as to deftroy life, not only in bodies of an aptitude to receive the poifon, but alfo in other fpecies of animals, which have no fuch aptitude. Hence, the poifon gen- erated in the clothes of the tick, when put into chefts or pack- ages, uncleanfed, in hot weather, may be fo concentrated or in- created by fermentation, as to kill almoft inftantly, the perfon who opens them. But an infeaious difeafe thus produced, will never fpread far, without the aid of a ftate of air which is pefti- lential. On the other hand, from thoufands of inftances. in books, and within the knowledge of Americans, who are annu- ally, monthly and weekly receiving infeaion from the Weft- iB6 tndies, we know that the infeaion foon difappears in a healthy conftitution of air. It may be fo virulent as to give difeafe to the perfons who firft approach it; but in thefe the difeafe is ex- tinguifhed. It fhould be further remarked, as a ufeful hint, that perfons removing fuddenly from frefh air to an infeaed place, are doubly expofed. The increafe of the peftilential caufes is ufually grad- ual ; therefore perfons who live within their operation, are in- fenfibly fitted, by the flexible texture of the fyftem, to fuftairt their effeas. But fudden changes are very dangerous. The body will hardly ever fuftain great changes in the powers of ex- citement, when fuddenly made. Hence the extreme danger of removing from frefh to infeaed air ; and fometimes, of removing from infeaed to frefh air. The fudden alteration in the ftimu- lus operating on the fyftem, may be as fatal in one cafe as the other. Another diftinguifhing circumftance, in peftilential difeafes, and one that decifively marks different grades of violence in the caufes, is, the manner in which the difeafe invades neighboring cities. It is always obferved, that during the prevalence of the plague, it attacks cities or towns at fome diftance, in one year, leaving other towns in the intervals between them, untouched ; the next year perhaps, or the fecond year after, it invades thofe intermediate towns which had efcaped. This is always the faa, and it has puzzled all authors who have related it; yet the faa has never been accounted for, as its caufes have never been un- derftood. Mead, who was not perfonally acquainted with this difeafe and whofe theory led him to explain all its phenomena by contagion, was greatly erabarraffed with this faa. He in- ftances the efcapp of Vicenza, in Italy, 1575, when Verona and Padua, one on each fide of Vicenza, were feverely affliaed; and in the next year, Vicenza was defolated,. when Verona and Padua were exempt. He could not explain how the infeaion^ which came from Trent, where the difeafe firft appeared, fhould pafs over Vicenza and reach a more diftant city. Erroneous theories are the fource of innumerable mifchiefs in fcience. The faa is a common one, and on a juft view of thfir caufes of peftilence, is very eafily explained. And what is 167 lurprizing, Procopius and Evagrius have recorded faas which afford a clue to the fecret, altho medical writers, from their days to the prefent time, have fuffered them to pafs without no- tice. Procopius mentions that the peftilence which began in 542, foread over the earth, but " if it paffed by a particular country at firft, or fllghtly affecled It, it foon returned upon it with the fame defolating rage, which other places had experi- enced." Evagrius alfo remarks, that " fome places were more (lightly affeaed ;" and in another pafTage he fays, that in fome cities a few families were feized the firft year, and the reft of the city, the year following. Here we have a clue to the myftery. The plague feizes firft the cities and towns where the general, or local caufes axe the moft powerful. Thus, the plague of 1575, which puzzled Mead fo much, commenced in Trent on the Adige, which, all geographers agree, is a moft unhealthy place. It next attacked Verona and Padua for a fimilar reafon, and afterwards Vicenza, the intermediate town. The general caufe, in the elements, had been four or five years in operation, producing a fatal fpotted fe- ver, in moft parts of Europe, continually increaflng in malig* nancy, until it arofe to the plague, and its crifis muft naturally be in places where it was moft aided by local caufes, or where the general caufe firft increafed to its full force. The flight peftilences mentioned by Procopius and Evagrius, were the precurfors of the fevere plagues to follow; precifely as in London and Marfeilles, a terrible plague was preceded, in a former year, with malignant fevers and a few cafes of plague. All hiftory affords a tiflue of proof, that the plague is never an ifolated difeafe, ftarting up fuddenly from infeaion ; but the trifts of a feries of violent difeafes. To this I challenge the par- tizans of fpecific contagion to name an exception. In America, we are able to folve the phenomenon of the et cape of places intervening between infeaed towns. We find, without an exception, that when two cities are infefted with pef- tilence, and an intervening place is not, if that intervening town is to be attacked the following year, the precurfors of the dif- eafe appear there, during the peftilence in the towns on each fide i68 of it. Thus "the late feries of plagues began in New-York in 1791, in Water and Front ftreets, where the local caufes were moft powerful. At this time, appeared fporadic cafes of bilious fever, more malignant than ufual, in various parts of the country,' every where, indicating the commencement of a peftilential ftate of air. In 1792, thefe indications continued, and in a few cafes ap- peared the fcarlatina, a new evidence of the reigning conftitu- tion. ' In 1793, the crifis arrived in Philadelphia, with ferious mor- tality ; and the indications of peftilence appeared in a great in- creafe of mortality, in many parts of the country. At the clofe of this year, New-Haven, which was to be next attacked, began to fhow the forerunners of the difeafe, in the fcarlatina, and in an increafe of mortality of about one fifth. In the next fummer 1794 appeared the bilious plague. In the fame feafon appeared the difeafe in Baltimore, diftant from New- Haven about 290 miles, while Philadelphia and New-York, in- tervening cities, efcaped. But let it be obferved, that a num- ber of cafes of the difeafe occurred in Philadelphia ; and New- York which was to be affailed in the next feafon, produced its precurfors, in about thirty cafes of violent bilious fever, ending in black vomit. Thus while on the extremes, New-Haven and Baltimore were feverely vifited, the approaching peftilence was announced in New-York, by a peftilential atmofphere, of a lefs degree of malignancy. In 1795 appeared the epidemic in New-York and in Norfolk, Virginia ; while Philadelphia and Baltimore, intermediate cities, efcaped, altho the heat and humidity of the feafon every where; rendered the country unhealthy. In this year the peftilential principle fhowed itfelf in New-London and Providence, in dif- tinaly marked cafes of the bilious plague. In 1796, fcattering cafes occurred in the northern parts of America. In Newburyport, peftilence prevailed, but preceded by an increafe of mortality, its precurfor. The fame difeafe prevailed in Bofton, New-York, and Charfefton, while inter, mediate towns efqaped. 169 In 1797, it appeared in Providence, Philadelphia, Baltimore and Norfolk, while New-York efcaped an epidemic, but a few very malignant cafes occurred, thowing the exiftence of the general caufe. So far as I can difeover, not a fpot on the globe has ever been vifited with peftilence, without its precurfors, fometimes one, two or three years, but always for fome months, before its in* ration.* If we had bills of mortality for Vicenza, in the years 1570 to 1576, or a hiftory of the difeafes in the town, during that period, I pledge myfelf that we fhould find, that during the plague in Verona and Padua, on each fide in 1575, fome ma- lignant difeafe prevailed in Vicenza, which greatly fwelled the bill of mortality for that year, and which announced, with al- moft infallible certainty, the approach of the plague. Inftead therefore of faying Vicenza efcaped the peftilence, the firft year, when Verona and Padua were affliaed, we fhould fay, the pefti- lence had commenced in lefs malignant diftempers, but its crifis in Vicenza was to be a year later. This is the whole myftery, and the uniformity of this feries of feas from the days of Procopius to this hour, renders it a matter of aftonifhment, that medical and other fcientific men, fhould have overlooked this great law of epidemic peftilence. Diemerbroeck remarks the faa, as well as Procopius and Eva- grius, that peftilence does not invade all places at once, but now this place, now that, and thus, in a feries of years, extending over the earth. See p. 50 of Diemerbroeck, and the foregoing hiftory of the plagues in Juftjnian's reign. But no author feems , to have obferved the progreffion of a general p'eftilential princi- ple, which, if it does not occafion plague in two contiguous towns, the fame year, occafions plague in one, and other malig- ^ nant difeafes in the other, which certainly indicate its approach. * Thucydides relates that the year of the plague at Athens was re- markably free from other difeafes preceding, and that the plague fel| - fuddlenly on the citizens. This may feem an exception to my remark; but is not; for all the neighboring people were collected into the city r which was befieged ; a circumftance alone fufikient to account for thf;' jfudden attack of the difeafe. Vol. II. X tyo To prove that infeaion has no concern in this laft mentioned phenomenon, according to the theory of Mead and others, it may be Obferved that the invafion of the difeafe in cities, is perfealy analogous to its invafion of a whole country. The difeafe rare- ly begins at one point and fpreads from that, Ijke the radii from the center of a circle, nor does it follow the nurfes and attend- ants of the perfons firft feized. On the other hand it ftarts up in various diftant parts of the town, among people who have no irt- tercourfe with the infeaed. To this, it may be alleged, the fe- vers'of Philadelphia in 1793 and 7 are exceptions ; but on crit- ical examination, I find they are not. That in New-Haven may be an exception. Thus Evagrius relates, that at the beginning, the plague feized particular families, fometimes only one or two, and the reft of the town efcaped, till the next year. Baronius from Gregory of Tours has well defcribed the firft progrefs of the plague, in 590, in the fouthern cities of France. He fays the difeafe was introduced by a veffel from Spain ; thfe firft record I can find of fuppofed importation by water. But when introduced, it did not feize every houfe at one time but left intervals. " Nee ftatim hoc incendium luis per domos fpargittir totas, fed interrupto certi temporis fpatio, ac velut in fegetem" flamma accenfa, utberti totam morbi incendio conflagravit.'* Vol. 8. 15. The metaphor here employed will appear ftriking to thofe who have feen a field of ftubble or the woods on fire,' in a windy day. The faa alfo corretponds exaaly with what hat been obferved in London, Marfeilles and other places, that the difeafe at firft ftarts up here and there, in remote filiations ; then fubfides for weeks perhaps, before it fpreads and becomes popular. Thus in Nimeguen, a few cafes occurred in November ; then there was an interval of fufpenfion ; in January, more cafes, and in March, the difeafe began to affume the fhape of an epidemic. Diem. p. 6. In London, fays Hodge, two or three perfons died, in one family, with fymptoms of the plague in 1664.—In the holidays, occurred another cafe—but a hard froft fufpended the aaion of the infeaion. The difeafed were at firft (hut up and guarded ; but to no purpofe. An order was iffued and enforced, that a red crofs fhould be fet on infeaed houfes, with thefe words inferibed, " Lord have mercy on us."—■ 171 In May and June the difeafe to ufe the author's own words, '* reigned doubtfully ;" fometimes in one part and fometimes in another ; and to ufe Hodges quaint expreffion, " it kept up a running fight," alternately infpiring hope and fear. This de- feription is lefs elegant than that of Baronius, but it expreffes the fame ideas of the firft progrefs of the plague. It is ftrange however that the writers fhould not have feen that their feas totally overthrow their own ideas of infeaion ; 'it being impoffible, that the operation of infeaion fhould be thus. fufpended, and afterwards revived. Froft totally annihilates in* feaion, altho it does not deftroy the atmofpheric caufe of difea- fes. Similar, in all refpeas, was the commencement of the plague at Marfeilles in 1720. At firft a few perfons died fudden* ly, then the difeafe difappeared, and the citizens fuppofed it to be ended. Repeated hopes and fears were revived by the alter- nate appearance and difappearance of the malady, for fome weeks in May and June. Yet the author who has related thefe faas made a book to prove its origin* from Levant infeaion 1 fo abfurd are men when they attempt to fupport preconceived fyftems !— In America, the peftilential fever has firft made its appearance, in a fimilar manner. It has every where been preceded by an in- creafe of mortality, and in moft places, has appeared in the fcattering, interrupted manner of the plagues before mentioned. In Philadelphia in 1797, and ftill more in 1798, fcattering cafes Occurred in June and July, feveral weeks before the arrival of the fuppofed fomifes, from the Weft-Indies. The fame faa occur- red in New-York in 1795 ; fome cafes appeared two weeks be- fore the arrival of the Zephyr, the fuppofed fource of infeaion. In Providence occurred the fame faa. The whole fecret of thefe phenomena, is, that infeaion has ufually nothing to do with the origin of the difeafe, according to the decided opinion of the learned Diemerbroeck, who faw the progrefs of the difeafe in Holland, and found it impoifible to af- cribe it, in many places, to that caufe. The reafon why perfons are feized, in remote and fcattered fituations and after different intervals of time, is, that the malig- nant principle is progrefflvt. In its ftate of increafe, it firft pro- t?4 duces difeafes iff a left violent type, and efpecially' all kinds of eruptive difeafes and catarrhous affeaions ; as influenza, meafles, fmall-pox, every fpecies of angina, petechial fever, and laftly plague. In winter, the fame caufe often occafions epidemic pleu- rify, or peripneumony of a moft mortal kind, and always bear- jng.fome likenefs to the epidemics of fummer and autumn. - In this progreffion or increafe of the peftilential principle, thofe perfons are firft feized, who have the leaft power of refilling its operation. This inability may proceed from various caufes. It may be occafioned by the natural organization of the body ; fome bodies being naturally more fufceptible of difeafe, than others. This indifpofition of bodies to repel the morbid aaion of air or Other caufes, is hidden from the eyes of man ; but that it exifts, We have proofs in every days experience. Other perfons are predifpofed to certain difeafes by artificial means. Thus every exceflive ftimulus, induces indirea debility, a fruitful caufe of difeafes. Hence the liability of robuft people (o all violent fevers. • Others may be expofed to peftilential difeafes from living in fituations, where the peftilential principle is affifted in its opera- tion by the debilitating qualities of morbid exhalations. Hence the early appearance and furious ravages of the plague in the nar- row ftreets of cities, and the filthy apartments of poverty. From thefe and other caufes, it happens that fome perfons are feized with peftilence, long before the bodies of otliers yield to the aaion of the deftruaive caufe. This will rationally account for all the variety of phenomena, which accompany this ferocious malady. The famereafoning applies to the angina maligna, which is on- ly another form of peftilence. Fothergill relates, that this dif- eafe appeared in London in a few cafes in 1739, and then difap- peared for a period of two or three years. It did not become epidemic, tho very infeaious. Works, p. 198. To confirm this hypothefis, I may remark that the plague is lefs infeaious on its firft appearance. This is admitted by Ruf- fel, on the plague of Aleppo, p. 19. 300, 297 and 315. At the fame time, it is agreed on all hands, to be more mortal, than '73 {ft its later ft ages. If infeaion were the caufe; the reverfe would be true, and the difeafe would be more mortal, in proportion to its extenfion, and the accumulation of infeaious matter. The firft cafes alfo would be equally infeaious, within the reach of their effluvia. Skenkius obferves that many perfons lived in infeaed houfes, where others were difeafed, for three or four weeks, without any ill effeas ; but they afterwards fickened and died. This he aferibes to an increafe of infeaion, and recommends, as the means of prevention, changes of clothes, and liberal ufe of wa- ter in the apartments. The faa may be explained on this prin- ciple ; or it maybe, and moft probably is, the effea of the flow .operation of the morbid air in inducing debility on particular fyf- tems. But it goes to prove that the infeaion of the difeafe is not fpecific contagion, but a vapor or acid, unfriendly to health, that is capable of every imaginable degree of force ; flighter de- grees of which require a long time to undermine the energies of life. Another confideration, which decides againft the origination of the plague from infeaion, is, that almoft all other difeafes, whether infeaious or not, exhibit the phenomena juft defcribed. It is not the plague alone that appears, this year in one town, and the next in a contiguous one ; or this week in one family, and the next in another ; or at the fame moment, in two fami- lies or towns, at fome miles diftance. The fame phenomena charaaerize dyfentery, meafles, anginas and other maladies which are infeaious ; and even intermittents, remittents, and fome others, which are not fpread by infeaion. Such was the manner in which the fatal dyfentery of the pe- riod about the year 1751, leaping from place to place, in differ- ent years, ravaged Conneaicut, for three or four years. The feme took place, with that difeafe, from 1773 to 1777. It was feattering from place to place, during a feries of years, and then almoft totally difappeared, for many years. Sometimes it fpread over a whole town ; at others, it was limited to a particular ftreet. In fome inftances, it fwept away a large part of a fam- ily ; in other inftances, families entirely efcaped. The fame has been its progrefs, during the laft five or fix years. In 1794, »74 U ravaged perby; m 1795, New-Haven. In t*98, it invaded a particular ftreet in the country, two miles from Stamford, waf infeaious and mortal, while the town generally efcaped. I The fcarlatina from 1793 to 1796, exhibited the fame feas* Its general progrefs was eaftward, but it often paffed by a town and firft feized one beyond it. The angina maligna in 1735 and 6 was remarked for the fame manner of appearance. It began in Kingfton, in New-Hamp- fhire, but inftead of a regular progrefs, ftep by ftep, it feized Bofton, fifty miles diftant, before it did Chefter, only fix miles diftant j yet its general progrefs was weftward, and hardly any place efcaped. Both this difeafe and the fcarlatina of the laft period, referabjed the plague in thefe other refpeas—they were moft mortal at firft ; and they affeaed families with very differ- ent degrees of violence, flightly troubling fome, and extiaguifh- ing the lives of all the children in others. The invafion of the influenza exhibits fimilar feas. Itfeize* at firft only here and there a perfon ; afterwards it becomes gen- eral, as at Edinburgh in 1762. See Effays and Obf. Edin. vol. 3. At other times, it has feized whole towns in a night; nor doea it proceed from town to town, according to their order on a map. Yet its general courfe is in one diretfion. I could produce a multitude of fimilar inftances of pleurify, and common autumnal fevers not infeaious, which appear one year, in one part of the country, and another, in another, with- out any vifible caufe for this variety. The inftances related by Dr. Buel of the town of Sheffield, are very diftinguiflied. See my Colfeaionon the Yellow Fever, p. 53 and 60. That town contains two large ponds, which make confiderable marfhes, that are fources of remittents. In 1794, remittent* of unufual vio- lence appeared within the miafmata arifing from the fouth pond —in J795, a fimilar fever raged in the vicinity of the north pond. This appeared at firft an unaccountable phenomenon ; but af- terwards the fever about the fouth pond in 1794 was afcribed to the drawing off the water, and expofing great quantities of pu- trefcible febftanecs to the aaion of heat. But ftill the difficulty is not removed. The north pond is admitted to be the moft Ill ufual and fruitful fbutce of difeafes; bat thefe did' not appear? in any extent, in 1794. The queftion then is, hot Why the; difeafes occurred, in that year, about the fouth pond, but wlry- they did not appear about the north pond, the principal focus of ficknefs in other years, and about which they raged with mel- ancholy effeas in the two following years ? No alteration is fog- g'efted to have been made in the circumftances of the north pond ; yet in One year, its exhalations were almoft harmlefs, and in thd next, they foread defolation over the neighborhood. See Medical Repofitory, vol. i* p. 458. In fuch cafes, juft reafoning leads us to fuppofe the general. ftate of the air or the local exhalations' or both, differ materially in the degrees of their force and aaivity, in different years; but to human eyes, the caufe of this difference is not often vifible. Sometimes a fevere epidemic will rage in one town and a mikdelr epidemic of a fimilar type in the vicinity. Thus Zimmerman obferves, that he has known a violent diarrhea follow a fuppref- fed perfpiration in September, in one town, when a dyfentery was epidemic in the neighboring country. To what fhall we im- pute this difference of difeafes, within a few miles, of each other, but to the different force of local caufes ? A general caufe, as a hot feafon, may predifpofe the body to a difeafe of a particular type, but this principle may be modified by innumera- ble circumftances on the furface of the earth. In analogy with thefe faas, is the manner in which peftilen- tial difeafes invade different fpecies of animals. In one place, horfes are feized ; in another, cows ; in a third, fheep. In one year cats fall viaims to peftilence ; and the next, hens and geefe ; but infeaion has no concern in thefe phenomena ; and we are to afcribe them to the various force of the peftilential principle in different feafons and places. The phenomenon now under confideration has not efcaped the obfervation of other phyficians in Europe. Stapfer, cited by Zimmerman on Phyfic, relates that the village of Oberwyl^ in the Canton of Berne, was attacked with a violent dyfentery in 1749, while the neighboring villages were free from the dif- eafe. In the next year, Oberwyl was healthy, while the neigh- 176 boring .Tillages were ravaged with the fame diforder, tho not fe- parated from the other by any mountain or foreft. I have occa- fion, fays Zimmerman, to obferve foraething like this, almoft every year. Tfie Englifh Editor remarks on thefe feas, that " the dyf- entery, like other contagious difeafes, is fpread by communica- tion with the infeaed perfons and clothes, and therefore it is not fjrange that one village fhould efcape, if its inhabitants were care- ful to avoid communication with their infeaed neighbors." Juft fo important are all the reafonings of the infeaion-ftick- lers ! The remarks are common-place and do not reach the point of difficulty. The queftion, is, to know why feveral villagca efcaped the difeafe, in the year when infeaion was near them, and were feized, the next year, when no infeaion exifted. The winter's cold totally extinguifhes the infeaion of that difeafe ; fo that the learned Editor is left without a refource. If any in- feaion had furvived the fraft of winter, it muft have been in the village firft infeaed, and in that place common fenfe and obfervation would teach us to look for a revival of the difeafe, the fucceed- ing fpring. But no ; that village is in perfea health, and others, where there had been no fomites, are laid wafte by its ravages.—. Such are the faas, and no theory of contagion is able to explain the caufe of their exiftence, in regard to this or any other difeafe. The dyfentery alfo has, in fome places, made the difcrimina- tion, obferved in the plague ; feizing perfons of a certain nation or blood, and not affeaing others who are equally expofed. In an epidemic dyfentery in Nimeguen, the French and Jews all efcaped. Van Swieten, vol. ifi. page 57. There is a fad related by Hodges and Diemerbroeck relpec-" ring the plague which muft not be omitted. Many perfons who had breathed the peftilential air of London and Nimeguen, went into the country, where they had the benefit of good air. Here they lived in health a month or two, then fickened and died of the plague. This is attributed to the latent poifon, which lies loing inaaive in the fyftem, then operates to the deftruaion of' life. This may be the caufe ; but is knot more natural toafcribe1 the faa to higher excitement from a pure air,- on a debilitated *77 fyftem, inducing indirea debility ? Or fhall we fuppofe that A peftilential atmofphere is moft ftimulant, and thar a removal in> to a pure air, induces direa debility ? Perhaps the following faas will throw fome light on the fubjea. In 1789, I left Hartford in Oaober, when the influenza was fpteading in that town, and was feized with the difeafe juft after' I arrived at Bofton. A fortnight after, I returned, with two ladies who had lived in Bofton. In a week after my arriving at Hartford, the town of Bofton was attacked with the influenza, and the two ladies at Hartford were feized at the fame time. The conclufion I draw from the fea, is, that the conftitution of air, producing the epidemic, is fome time in operation, be- fore its effeas are vifible, gradually inducing a difpofition in the fyftem to that difeafe 5 and as it is progreflive, it requires about the fame time to run through its courfe in one place as in another, and is not always interrupted by local caufes. But the moft incontrovertible evidence, that infeaion is no? the primary, controlling caufe of the plague, arifes from the man- ner in which that epidemic ceafes, If infeaion were the principal and fpecific caufe of its propa- gation, it muft rage forever, or as long as any of the human race flioifild fervive to receive it; for the longer the difeafe exifts, the more extenfive muft it be. This conclufion is inevitable ; for if infeaion fpreads the difeafe fo rapidly, that one or two difeafed perfons diffufe it in a few weeks over a city, the fame principle muft, in a given time, extend it over the whole earth, unlefs its operation fhould be arretted by a fuperior caufe. And as one difeafed perfon is fuppofed to infea more than one healthy per- fon, its progrefs muft be accelerated, in a duplicate, triplicate and quadruplicate ratio to its diftance from its fource. Its ve- locity alfo muft be increafed, not only by numbers in a crouded city, but by an augmented virulence, until all the inhabitants fhould be deftroyed. But all this is contrary to faa. Moft plagues are modified and regulated by the feafons ; but the ceffation of peftilence in different countries, is in different feafons, and feems to depend on oppofite principles. In Egypt, a warm country, ncrer reached by what may he called coldt the Vol. JI. Y 178 plague begins in winter, as in December, January or February" j after the Nile has fubfided within its banks, leaving extenfive plains and numerous canals, expofed to a hot fun ; with a flimy furface and ftagnant water in abundance, on the face of the country. During this period alfo blow the foutherly and fuffo- cating winds, hot and dufty, from fandy defarts, which may augment the caufes of difeafe. On the other hand, the difeafe ceafes in June, when the Nile overflows its banks, fpreading frefh water over the face of the Country; at which time alfo begin to blow the cool refrefhing elyfian breezes from the north or Mediterranean fea. Hence it is obvious that the exiftence of the difeafe depends on the general ftate of the atmofphere; for the inundation of the Nile certainly does not wafh away the infeaion from the houfes and clothes of the fick. On the other hand, the plague ceafes, when the infeaion is moft general) and this is true in every inftance. It may be faid, that the plague arifes from putrid exhalations in Egypt, and the reafon why it ceafes, on the rifing of the Nile, is, that the expanfion of frefh water over the country and a pure northerly air, dcftroy thefe exhalations. In this obfervation there is truth ; and it would account for the origin and the ceflation of the plague, if it was an annual difeafe, regularly influenced and entirely governed by the fea- fons. But here again we are overthrown; for in moft years, putrid exhalations, which always exift at a certain feafon, do not produce the difeafe. Thus we are driven to feek another caufe, which is not influenced by feafons ; and to fuppofe its co-operation with hot winds and ftagnant waters in the generation of the difeafe. This is moft indubitably the fea. Again, the plague in Syria, farther north, where fome win- ter's cold is experienced, begins in fpring, as in February or March, and ends in June and July, during the moft exceflive heat of the fummer. This is the fea, from Aleppo to Jerufa- lem, and has been, from the earlieft records extant. Here then different caufes, extreme heat and drouth, feem to control the rage of the plague. But does heat deftroy infeaion r Never, unlefs by combuftion. No degree of heat that is ever *79 felt in the tropical regions, or in America, has ever mitigated the force of infeaion, but always has increafed it. Now we know, that the heat of Syria, never exceeds in degree what is annually experienced in the Weft-Indies and the United States, to the 42d degree of latitude certainly, and probably to the 44th. In one refpea Syria differs from this country ; the fummers are longer than in the northern ftates of America, and the climate fubjea to drouth. But it cannot be the duration of the heat which deftroys the plague ; for that difeafe ceafes at the very be- ginning of fummer. It abates in June, and rarely appears, to any extent, as late as Auguft. Nor can we concieve why drouth in Syria fhould put an end to the epidemic, for in moft other countries, it has not that effea. In Europe and America, ex- treme drouth has very often inflamed its violence. In this inftance then we find no caufe for the ceffation of the plague, in the weather or feafons, which we are able to compre- hend. We know the uniformity of the faa ; and all beyond this, is conjeaure. Infeaion can have no concern in the effea; unlefs on fome principle hitherto unknown, cool weather generates it and heat deftroys it, contrary to feas in all other countries. Certain it is, that the plague at Aleppo, Damafcus, Said, Je- rufalem, Latakia, and on all the Syrian coaft, ceafes in ex- treme hot weather, and when the infeaion is in its utmoft extent and violence. In Italy, Conftantinople, in all Europe and the temperate lat- itudes of America, ordinary phgues yield to cold ; that is, they ceafe as epidemics of that form ; but the general caufe never fails to fhow its influence, in giving to the diforders of winter, fome of the general fymptoms which charaaerize the epidemic of the fummer. This proves that, in common peftilence, morbid ex- halations aid the atmofpheric caufe in producing the epidemic ; and that it is not fpecific contagion which contributes to fpread the difeafe, for this is not influenced by cold ; but it is morbid exhalations, that yield to cold. Hence, in northern climates, cold fufpends the aaion of the two fubordinate caufes of peftilence, morbid exhalations and infeaion j and this is ufually fuflkient to check the epidemic. i8o But that the great primary caufe, is not affeaed or rather foti- dued by cold, is apparent from thefe faas ; that altho the plague, in its peculiar autumnal form, is fufrended, yet the difeafes of winter, as pleurify and peripneumony, wear the fame charaaer ; :which can be occafioned only by the continued aaion of the fame caufe. Further, fome plagues have not yielded to cold, as I have before obferved. Several inftances have occurred, in which the difeafe has run through all the feafons without interruption or abatement. This fea demonftrates that the primary caufe, ex- ifting in the effential properties of the elements, may be of vari- ous degrees of force, and at times does aaually arife to a degree, capable of producing and continuing that diforder, not only with- out the aid of morbid exhalations and infeaion, but in defiance of cold. In conformity with this idea, is the fea that a peftilence which begins the earlieft in the feafon, is the moft mortal. This is a- greed by P. Alpinus, Van Swieten and Sydenham, " Minus faeva eft, quo tardius illuc acceffit, viderique incepit ; ita ut quo tardius venerit, eo mitior ac brevior fit judicanda," fays Alpi- nus, Rerum Egypt, Vol. 3. 70. The reafon of which is, that in proportion to the ftrength of the elemental caufe, it begins to exhibit its effeas early ifi the feafon ; that is, with the leafl aid from heat, noxious effluvia or other local caufes.—If the general contagion of the atmofphere is very powerful, its effeas may ap- pear even in winter, in oppofition to cold ; hence the juftnefs of Diemerbroeck's remark, that peftilence beginning in winter, is the moft fatal, ff, on the contrary, the general conftitution of the air is lefs hoftile to life and health, it will not produce an epi- demic peftilence, till it is alfifted hj great heat and local vitiation : of the air ; therefore the difeafe will not appear, till late in the feafon. Something like this, en a fmall feale, has charaaerized the different epidemics in Philadelphia. 101793, the precurfors of the epidemic were light, and the firft cafes did not appear, till the laft of July or beginning of Auguft. In 1797 and 98, the firft cafes occurred in June^and the difeafe in the latter years, was marked with by far the moft malignant fymptoms, altho the J* I timely evacuation of the city prevented bills of mortality equal to that of 1793. In New-York, this circumftance, rt is believed, has been lefs noticeable ; but it may be remarked, that in the years of the epi- demic, the firft cafes occurred in the laft week in July, and in years, when a few fporadic cafes* only have appeared, they have not occurred till many weeks later. Betides, it is very obvious that the difeafes of 1795 an^ 6, if not of 1797, were powerfully influenced, in their commencement,.by local caufes ; as great rnaflesof putrid matter, in the parts of the city, where the firft cafes occurred, and where the epidemic exhaufted its principal force.-— In general, it may be obferved in our climate, that if a malig- nant fever does not appear, in a city, till late in Auguft, the cit- izens need not apprehend very general defolation. If cafes occur early, as in June, there is ferious ground for apprehenfions.of danger. The only exception to thefe remarks, is, when the fea- fons fuffer fome great, unufual and fudden viciflitudes, which, du- ring a peftilential period, may overwhelm a city with almoftin- flantaneous calamity.—Such may be a fudden invafion of heat in Auguft, after preceding cool weather. In general it is a juft remark, that as the force of the peftilential principle, is of various degrees, in different periods, fo when it is moft powerful, it attacks men the earlieft in the proper feafon, and is deftined to be the moft deftruaive. The preceding feas and conclufions feem fufficient to eftablifh the great point, that neidier contagion nor infeaion has ever bad much influence in originating or propagating peftilential epidemic difeafes of the autumnal kind. * The advocates of the fpecific contagion of the plague do not ad- mit that the true plague ever appears in fporadic cafes. They think, if it once appears, its contagion muft of neceffity, fpread it. This is all a whim. I believe, with Dr. Mitchell, that any difeafe of the worft type, may be generated in the body, folely by a derangement of the functions of the ftomach and inteftines,and the poifonous air extricated from food. But that fporadic cafes of plague may occur and do occur very often, I have not the leaft doubt. During the late war, in 1776 or 1777, two brothers by the name of -—- arrived from the army at Greenwich in Conneaicut—one had a malignant fever, with glandular tumors; the other was his nurfe and in good health. The fick man di- ed foon after he arrived, and in lefs than 24 hours, his brother was alfo in his grave. This was true plague ; but no other attendant was in- feaed.— l82 But objections remain to be anfwcred. It is alleged that the plague begins in maratime places and thence fpreads into the coun- try adjacent. Thus it is afferted by the college of phyficians in Philadelphia, that the peftilential fever in America " commen- ces invariably in our fea-ports, while inland towns, equally expo- fed to the ordinary, caufes of fever, efcape." Memorial, dated Dec. 5, 1797. Pliny, a great obferver of feas in the natural world, goes far- ther and afferts, " That peftilence is obferved always to proceed from fouthern regions towards the fitting fun ; nor does it fearce- ly ever happen otherwife, except in winter." Lib. 7. Cap. 50. Mead and the author of Traite de la pefte have cited this opin- ion with approbation. By the words of Pliny " a meridionis partibus, ad occafum folis," muft mean from Egypt and the Bar- bary coaft, towards Italy, Gaul and the other weftern parts of Europe. From thefe feas, is inferred a ftrong argument in favor of the propagation of that difeafe by contagion. With deference to thefe great authorities, not one of thefe af-, fertions is accurate. That the plague generally appears firft in fea-ports, is a juft remark, and according to the laws of nature, it muft be fo, without infeaion. But to this rule there are many exceptions. The general plague in the days of Thucydides origina- ted in Ethiopia, near the borders of upper Egypt, not a fea-port. The violent plague in 252 began in the fame region ; as didj that of 1736. The plague of 542 began in Lower Egypt, between Pelufium and a morafs, called the Serbonian bog, at a diftance from the port of Pelufium. It fhould have been mentioned that the mor- tal plague in the reign of the Antonines began in Seleucia, on the Tigris, far from the fea. The black peftilence of 1348 origin- ated in China. That of 1450 in fome parts of Afia. The pefti- lence of 1348 began, when it firft appeared in France, in A- vignon, not a fea-port ; as did that of 1482. The plague of 1575 m Italy, began at the northward, in Trent, and proceeded fouthward, contrary to the aflertion of Pliny; and every one **3 sknow Trent is not a maritime place. The plague in Holland in 1663, began in Heufden, not a. fea-port, but on a river amf near a morafs. In 1702, a plague broke out in Poland, far from the fea. With refpea to the United States, the aflertion of the College of Phyficians muft ftand or fall, according to the definition of the fevers which have appeared in the country. If no peftilence has ever appeared, except in fea-ports, we muft affix fome other name to the mortal epidemics that vifit the interior of our coun- try. Certain it is, contrary to the ftatement of the College of Phyficians, that the true yellow fever, and fo called at the time, prevailed in Albany in 1746. About the marfhes in the interior of our country, an epidemic bilious fever has times without number, raged as fatally, as Cver it did in Philadelphia, deftroying life in three or four days, at- tended with all the charaaeriftic fymptoms of yellow fever and carrying off almoft every perfon, within the region of its atmoG phere. This has happened, about fome of the lakes in the ftate of New-York, every year fince the prefent peftilential period com- menced, and whole villages have been depopulated. If the Col- lege of Phyficians choofe not to call this difeafe yellow fever, I cannot help it ; but fore I am, if it is not that fpecific diforder, it is one equally defolating, and as little entitled to be fathered on the country, as any fpecies of plague whatever. It is a fea alfo that the bodies of thofe who perifh by that fever near rivers and lakes, are, if poflible, more yellow than in cities. But what utterly difproves the aflertion of the College of Phy- ficians, is, that the fame peftilential diftemper which has lately affliaed our cities, appeared among the aborigines of this coun- try, before it was fettled by the Englifh, before the Weft-Indies were fettled by the Englifh or French, and before a tingle veflH. from the iflands had ever reached our fhores. To confirm this fea, it is well known that the fame difeafe has often vifited them, fince the Englifh fettlements, and in fituations and under circum- ftances, when it was not poflible for them to receive it from infec- tion, as at Nantucket and Martha's Vineyard in 1763, andfeve- ral times, in the limits of the prefent ftate of Rhodfi-Ifland. 184 The Onandagoes in the ftate of New-York, three or four hun- dred miles from a fea-port, about eighty years ago, were attacked with peftilence, which wafted the tribe ; and the place where their village was then built, has, on the account of that mortality, been ever fince abandoned, and is now overgrown with trees. The fame happened among the Senecas at a later period.1 - What the difeafe among the Onondagoes was, I am not inform- ed ; it might have been the fmall-pox ; but the country where it happened, is now fubjea to mortal bilious epidemics, which kill in three days, and turn the body as yellow as faffron. Befides the great plague of 1618 is known to have been the true infeaious yellow fever, and fo was the fever of Nantucket in 1763, nei- ther of which could poflibly have been imported. About fixty years ago, a great mortality happened among the Indians, on the north eaft of a fmall ftream, a little fouth of. Eaft-Greenwich, in the ftate of llhode-Ifland. The difeafe was fatal to almoft all who were affeaed ; but it was local, and in- feaious, for a law was paffed that no perfon fhould go from one fide of the river to the other, and the Indians on the oppofite fide remained in health. This place was no fea-port, but an In- dian hamlet ; and no pretence of importation is fuggefted, nor does it appear, that any whites were affeaed. • ' About twenty-fix years ago, a malignant bilious fever attack-^ cd the Indians, at Quidnefit neck, in North-Kingfton, in the fame ftate, and moft who were feized, perifhed. It attacked alfo a few families of whites, but with lefs mortality. North- Ivingfton is a fea-port- but there is no fuggeftion of foreign origin. M. S. of Mofes Brown of Providence. Fn>r:i thefe faas let the public judge how little reliance can be placed on general affertions even of learned and relpeaahle foci- eties, when made without a critical examination of the fubjea. It is proper that I fhould here take notice of an aflertion, found in a number of authors. " That Thucydides relates the plague, in his days, to have fpread from Ethiopia by means of contagion, infeaion or fomites." The learned Diemerbroeck has fallen into this miftake. p. 48. Galen'is more correa, when he fays, that peftilence fpread by the corruption or infeaion of the air. This idea, tho nq$ the expeflion, is accurate. The truth is, Thucydides does nol fay, the diftemper fpread by infeaion or contagion. A literal tranflation from the Greek is as follows. " It began as it is re- ported, firft from Ethiopia, above Egypt ; then it fell on Egypt and Lybia, and a great part of the King's dominions (Perfia.) It thenfuddenly invaded the ckyof Athens andfirftthe Pieraeus." In the paragraph preceding he fays, the difeafe had prevailed in many regions firft and efpecially at Lemnos ; but does not hint at infeaion or contagion as the caufe. The obfervation of Pliny, that peftilence originates in fouth- ern climates and proceeds northward and weftward, is generally, but not always true. Alexander Ruffel tells us, the peftilence in Aleppo in 1719 came from the northward ; and many au- thors relate that it appears in Conftantinople or Smyrna, before it does in Egypt. This may be partly owing to alterations in the Tutkifh cities, fince Pliny's time. But on juft principles, the fea is rationally explained. If a particular- ftate of air, favorable to the propagation of that dif- temper, muft exift, before it can become epidemic, which is ad- mitted by the friends and foes of contagion, then fuppofing this general peftilential principle to exift, at a given time, in equal force, all over the earth, or any portion of it j it muft follow inevitably, that this general caufe will produce the worft difeafes^/f/y? in climates and fituations, where the moft powerful local caufes exift, as heat, moifture, and all kinds of deleterious exhalations. And for a moft obvious reafon ; the debility of the human body muft be firft induced in thofe fituations. This is a complete folution of the fea mentioned by Pliny ; and he himfelf juftifies this explanation of it, for he excepts from his own general rule, the peftilence that appears in winter, a circumftance paffed over by Mead. Now the reafon why a plague beginning in winter does not follow the courfe of one be- ginning in fummer, but appears fometimes in northern climates firft, is, that fech a peftilence does not require the aid of con- tingent caufes, as noxious exhalations. It is independent of lo- cal caufes, and induced folely by the effential qualities of the at- mofphere ; it may therefore appear. firft in any place or cJimatq ;Vol. II, £ i86 whatever, according to that ftate of air. This happens only in great plagues which feldom occur. Thefe obfervations apply alfo to the objeaion that peftilence firft appears in maritime places, as mentioned by Procopius, and others. It is a fea known to every medical man that humidity is a caufe of debility. Hear what the learned Zimmerman fays on this point. On Phyfic, vol. 2. p. 10c. " The humidity of air weakens a man fuddenly ; it relaxes the folids, and of courfe weakens the circulation, fo that the fe- cretions are carried on with difficulty. The infenfible perfpira- tion is checked, the moifture paffes in through the abforbingpores of thefkin, and the patient feels a laflitude and heavinefs, which deprive him of all his gaiety, and render the mind as oppreffed as the body'*—" Damp fituations are, in every country, un- healthy." p. ioz. There is not a perfon living who cannot teftify to the truth of thefe remarks. Hence the languor which deprefles man, in a hot fultry day, with a foutherly light air, loaded with vapor. Hence this ftate of the air, when of long continuance, never fails to generate epidemic diforders ; and if it occurs, during a peftilential conftitution, mankind feldom efeape the ravages of the plague. It may be faid that the inhabitants of maritime towns, are lefs expofed'to this fource of debility, than feamen, who are in general remarkably healthy. To which 1 anfwer, that the or- dinary moifture from fea air never of itfelf produces difeafes ; and at fea, there exifts no exciting caufe, as morbid exhalations, unlefs in fhips of warandcrouded tranfports, in which difeafes often proceed from human effluvia. But I queftion whether the bodies of feamen poffefs the fame firm texture as thofe of laboring far- mers in the country. Certain it is, that feamen are in general not fo long-lived men, as farmers. This is afcribed to thek ir- regular and fevere fatigue ; but I fefpea it more owing to the in- ceffant operation of the debilitating powers of moifture. Whatever may be in this, it is certain that moifture of itfelf 'in- i8? duces debility, in a greater or lefs degree, tho not difeafe ; but When its aaion on the fyftem is combined with the operation of morbid exhalations, which abound in cities, efpecially near navi- gable water, together with the frequent alternations of heat and cold, occafioned by the contiguity of land and water; we are not to be furprifed that cities on the borders of the ocean, and the banks of rivers, are the firft to be attacked with peftilence. We might, without the aid of feas, prove a priori, that this muft generally be the cafe. Hodges mentions that the London plague of i 665 fpread into the adjacent country, efpecially along the Thames ; but he takes care to afcribe this to infeaed goods, and not to humidity—a- nother proof of the mifchiefs of theory. Indeed the circumftance that next to large maritime cities, the towns fituated on the borders of rivers or lakes, are the moft fe* verely harraffed with epidemics of a fatal kind, efpecially autum- nal difeafes, is an evidence of the truth of the fame principle. Wherever we turn our eyes, we fee autumnal difeafes, from Am- ple tertians to the plague, moft frequent and moft deadly, in low fituations, under the combined operation of heat, moifture and different fpecies of noxious exhalations. It is therefore as un- philofophical to deduce, from this fea, arguments in favor of the foreign origin of the plague, as in favor of the importation of many other malignant difeafes ; for the fame phenomena attend them all—they all appear firft, and are moft epidemic and fatal, in the vicinity of water. This is their general rule, to which exift fome exceptions, as well in regard to the plague, as to other bilious complaints. But the difcovery of a general peftilential principle, extend- ing over a whole hemifphere, or the whole globe nearly at the fame time, or with a rapid prOgreflion, folves all the difficulties on this fubjea. Had Pliny known, that at the moment a fevere plague appears in Egypt, the difeafes of all Europe, or all the world, affume unufual malignancy, or other contagious and in- feaious epidemics appear, in every quarter, to the diftance of a thoufand leagues, his remark would have been equally juft, as to the origin and progrefs of the plague, but it would have opened to him new caufes of its origin, and a more juft and philofoph* log ical view of the phenomenon. This is a difcovery which prof- trates all theories of fpecific contagion, and reduces the influence of infeclion to its juft meafure. Another h&. Foreftus has declared that in peftilence, three times the number died in wet weather, as in fair and dry weath- er ; the infeaion being lefs eafily difperfed, in wet weather, which is evident from the fmoke of chimnies. Van Swieten, vol. i6. z6. It is well known in America, that while the weather is hot, rains and raoift air greatly multiply cafes of peftilential fever. In 1720 a ftorm of thunder and lightning at Marfeilles, late in July, was followed by a great increafe of the plague. Traite de la pefte. Every one knows that the air, along the borders of the ocean, corrodes iron and other metallic fubftances. Is it not then quef- tionable whether the feline acid, which impregnates the maritime .air, has not fome deleterious effea on the human body, when combined with other vapors from the earth ? Are we yet ac- quainted widi the effential properties of all the poflible combina- tions of aerial fubftances ? Again; Mead has remarked, that countries and cities which have had moft commerce with Africa, as Marfeilles, have been moft frequently aftliaed with the plague. A French author, he lays, reckons 20 plagues that have infefted Marfeilles, notwith- ftanding its healthy fituation. In oppofition to this, it may be proved by feas, that the cit- ies, in the interior of Germany, that never had any trade or conneaion with Egypt, ufed formerly to be harraffed with that difeafe, nearly, if not quite as often as the maritime ports of Eng- land, France, Spain or Italy. Any man will learn this, who reads the whole hiftory of that calamity, inftead of that of a few detached inftances. As to the twenty plagues of Marfeilles, afcribed to the trade with Egypt, I would obferve, that I can produce the hiftory of near double that number of violent plagues in London, before that city had any trade or conneaion with Egypt. Equally, ill founded is the idea of medical writers that the yel- low fever of the Weft-Indies was brought firft from Siarq. " Mai- 189 adie de Siam*" is the name given to it by French phyficians ; and this improper name, will ferve to perpetuate the error, while it fhall exift as a monument of ignorance and falfe philofophy. This pretended Siam fever was the peftilence of the Indians, on this continent, before the Weft-India Iflands were fettled by the French or Englifh. Another extraordinary aflertion of Mead, is, that " the north- ern nations of Europe, before their conneaion with Africa in trade, grew populous more rapidly, than in modern times." I will not conteft the aflertion, as it regards the degree of pop- ulation of thofe countries, in different periods. Authors differ in opinion on the fubjea of the ancient population of Europe, and no certain documents or feas exift by which the point can be afcertained. But the implication neceffarily deduced from Mead's aflertion, is, that the plague is more frequent and deftruaive in the north of Europe, fince a trade has been opened with Egypt, than be- fore ; for on this principle only would he account for the redu- ced population of modern times. If this is what he meant to infinuate, the aflertion is not fimply inaccurate, but abfolutely falfe. From the firft accounts we have of Ruflia, Poland and the Baltic regions, to the firft opening of a trade with Egypt, in modern days, plagues were much more frequent and fatal in thofe countries than they have been, within, the laft century, fince a con- ftant trade has been carried on with Egypt and every part of the Levant. For the truth of this aflertion, I appeal to feas— In the year 1485, the Englifh firft opened a trade to the Medi- terranean, efpecially with Italy, and a conful was appointed, re- fident at Pifa. The aa of appointment by Richard 3d. con- tains this pafTage " whereas certain merchants and others, from England, Intend to frequent foreign parts, and chiefly Italy, with their fhips and merchandize"—Before this, England had little or no trade, dlreSly with foreign countries. All her trade was con- duaed by Lombards, Genoefe, Venetians and the Hanfemerch- ants. There was no dii ea trade to Egypt and the Levant. About the year 1511, Englifh fhips began to frequent Sicily, Candia, Chios and the Syrian coaft ; but this was accounted a igo Tery hazardous voyage, and fhips feldom made it in lefs than a year. In 1535 Englifh feaors firft fettled in thofe countries. See Anderfon's Commerce, vol. 1. 683. vol. 2. 79. Rymer's Federa, vol. it. a6r, and Hackluits Voyages,vol. 2.96. Now, the fea is, that the plague was as frequent and fevere in England, Denmark, Sweden and Germany, in the tenth, Seventh, twelfth and thirteenth centuries, before any foreign trade exifted, as in any later period. Not to mention the uni- verfal plague in the days of Vortigern, about 448, which never has been exceeded in extent and violence, unlefs by the black peftilence of 1348. The Levant Company was firft eftablifhed by Queen Eliza- beth in 1581, and the aa of incorporation expre'fsly ftates that " Sir Edward Ofborn and his affociates, the perfons incorpora- ted, had at their own great cofts and charges, found out and opened a trade to Turkey." Before that time the commodities 6f Egypt, Syria and Turkey were all imported from Italy, in Venetian or Genoefe fhips. The commerce of the North of Europe from the year 1200 to 1500, was almoft wholly in the hands of the Hanfeatic Con- federacy ; but on careful inveftigation, I cannot find the leaft trace of a direa trade to the Levant, by the towns in that league. Indeed before the difcovery of the mariner's compafs, in the 14th Century, all trade was carried on by coafting. Hif- tory records more than one hundred general plagues before that difcovery. So totally falfe is the aflertion of Mead. But fay the College of Phyficians, in the memorial before cited, " proper health laws, ftrialy enforced, have latterly pro- teaed the commercial parts of Europe from its ravages." This is a point of importance, and while the aflertion ftands unfup- ported by proofs, I am at liberty to deny the truth of it, and there leave the queftion, as fair on one fide as the other ; for I cannot prove a negative. If however health laws have produ- ced the effea alleged, it is very ftrange that the plague did not difappear at a much earlier period. The inftitution of health laws was as early as 1484, and it appears they were firft introduced at Venice. If thefe laws have 191 ever prevented an epidemic plague, it is very ftrange, that they were ineffeaual in Venice and other parts of Italy, for near two hundred years, as they certainly were. It is indeed wonderful that, during the 16th century when all Europe was almoft con- tinually ravaged by that difeafe, and down to the clofe of the laft century, no man could be found to devife a law, and no police, to enforce k, fo as to air eft the progrefs of the plague in Italy. Yet fuch was the fea. The firft ftatute, I believe, in England to reftrain the progrefs of infeaion, was in 1604, in the firft feflion of James I. 31. The regulations attempted by the proclamation of Queen Eliza- beth in 1580, before recited, prohibiting the enlargement of London, and the refidence of more families than one in the feme houfe, could not, from the tenor of them, be carried into effea. The ftatute of James limits its prdvifions to the con- finement of the fick to their houfes, a breach of which was made felony. An enforcement was attempted in the fubfequent plagues, and efpecially in 1665, but without the leaft good effea, as to the city at large, and with a very ill effea upon the difeafed and their families. It is certain however that a ftria execution of fuch a law, would arreft the progrefs of infeclion, for the infeaion of the plague is found and admitted on all hands to be confined to contaa or very near approach, fo as to be received by the breath of the difeafed. If therefore the difeafe were propagated by infeaion only, fuch confinement of the fick would check its progrefs, if not annihilate it. We know by repeated experience in America, that there is not the leaft difficulty in putting an end to a difeafe arifing folely from fpecific contagion ; and it has often been done in cafes of the fmall-pox. Hence the inefficacy of the law of James I. after repeated trials in the plague, is a ftrong evidence that its propagation depends on fome Other caufe than infeaion. From 1604, to the reign of Queen Anne, no general laws were enaaed on this fubjea, as far as I can difcover from the printed ftatutes. In the 9th year of Queen Anne, 1709, paf- fed the firft ftatute enjoining veffels to perform quarantine ; at leaft I can find none earlier. This was repeated by 26th. 192 George 2, 1752, anew ftatute on the fubjea, which was after-. wards amended by the 29th of the fame reign. Now itfo hap- pens, that the plague ceafed in London in 1666, forty-three yfcirs before a general quarantine was inftttuted. Particular lawsv Had beeh paffed before, on emergencies, as in 1664, when all importation of goods from Holland, was prohibited, on account of the plague, then in Holland ; but without effea. The truths then, is, fo far as regards Great-Britain, now the moft commer- cial country on earth, and at the time in queftion, the moft com- mercial, next to Holland, the plague entirely ceafed and difap- peared, 43 years before the exiftence of quarantine laws. If any miftake occurs in this ftatement, it muft proceed from want of materials—my enquiries are limited to Blackftone and the printed ftatutes at large, the only documents I poffefs on that, fobjea. In the courfe of my reading, I have found but two or three* inftances, in which it has ever been fuppofed that health laws have preferved a city from peftilence. Mead mentions two inftances ; one at Ferrara in 1630, where every perfon, feized with the difv order, was immediately removed to a Lazaretto; which being done in feven or eight inftances, the difeafe was checked and dif- appeared. Another inftance he mentions was at Rome in 1657, where the perfons firft feized were removed to Lazarettos and their famv ilies to hofpitals without the city, and the city was foon freed- from the diforder. He fuppofes further that the difeafe was fuf- pended a whole fortnight in Marfeilles, in 1720, by the famet means. I have no account before me of the origin and progrefs of the plague, in Italy, 1630 and 1657, except the fketches found in Mead's works, but wherever I can obtain a correa account of this difeafe, mentioned alfo by Mead, I find his ftatements are imperfea and erroneous ; I therefore place very little dependence on them. That the plague in Marfeilles was flopped a fortnight by regulations of policy, is not true. The difeafe appeared in the preceding autumn, and was fufpended five or fix months by the winter. When it appeared in the month of May 1720, wri- *93 ters fay, the firft cafes were among thofe who had intercourfe with the thin and goods from Said ; but all thofe goods were prohibited to be carried into the city, and fubjeaed to fifteen days retreat and purification. The porters who had concern with them were confined. Some weeks after, in the month of June, cafes of the difeafe appeared in the city ; all precautions had proved fruitlefs ; as the hot weather came on, the difeafe ftarted up here and there in the city, among perfons who never had any concern with the thip or the goods, or the infeaed ; it then fubfided ; then again appeared, in the manner before related, Whether the perfons feized in May contraaed the difeafe from the goods or foul air of the fliip, or not, is not material ; for the goods were cleanfed, and all the difeafed confined to the hoipital, and all the porters fhut out from the city. Yet when the difeafe appeared in the eity, no perfon could tell how it came there ; many were feized who had never been near infeaion ; and hence the populace refort to fuppofition to account for its or- igin—they fuppofe the difeafe had come from the goods after they were cleanfed, tho they had no evidence of it. Betides I have before remarked under the year 1720, that the goods could not be infeaed, for it is admitted on all hands that they were fliip? ped at Said, when the difeafe was not in that port. The fhip's hold might have generated foul air on her pafTage, and the firft perfons conneaed with her might have contraaed a peftilence from that air, which is not an uncommon thing, in fuch a very fickly period, as that was, when mortality was increafed all over Europe and America. But the truth is, had that air been the caufe of the plague in the city, the difeafe would not have been fufpended for fix weeks, but would have made a regular progrefs from one patient to another. But no ; it difappears for fix weeks, and then breaks out in parts of the city remote from the fuppo- fed fource of infeaion, and among people who had not been near that fource. So inaccurate and inconfiftent appear all accounts cf the contraaion of epidemic difeafes from fomites, which I have been able to inveftigate by full and authentic documents. This fhows how little reliance wc can place on partial ftatement?, ivade to fopport favorite fyftenjs. I therefore am perfuaded that Vol. II. A a »94 the cafes mentioned by Mead of the effeaual reftraint of the plague in Italy by removing the fick, are not fully ftated, and that an accurate enquiry would prove the fuppofed effea to refult from other caufes. The following feas will furnilh a more rational folution of the phenomenon. In the United States, ever fince the commencement of the prefent conftitution of air, that is, from 1790, fporadic cafes of our peftilential fever have occurred, not only in citjes, but in va- rious parts of the country, more or lefs, every fummer and au- tumn. In 1792 occurred a number in New-York ; alfo in 1794 when one cafe exhibited infeaion ; and in 1797. Of a- bout thirty cafes perhaps, in each year, fome of them were ex- ceflively violent, highly marked, and in a degree, infeaious. In 1791 and in 1796, feveral hundred cafes appeared, yet thedit eafe was not epidemic, but local, and the bufinefs of the city was not fufpended. Now had every perfon, the moment of his feizure, been conveyed out of the city to a hofpital, the efeape of the cky, in each of thefe years, would vulgarly have been afcribed to that circumftance. This was doubtlefs the cafe in Ferrara and Rome, and this is unqueftionably the folution of the faa, that the cafes in the Italian cities, were fporadic cafes, which always occur in the neighborhood of the plague. This difeafe,, in the years mentioned, raged in other parts of Italy ; the cafes men- tioned by Mead were fporadic cafes, indicating a peftilential con- ftitution of air, extending to thofe cities, but of a lefs malignancy, and too mild to produce a general peftilence in thofe places ; it affeaed only a few perfons of habits moft fufeeptible of it ; and to thefe it probably would have been limited, had none of them been removed. A fimilar fea occufred in Philadelphia in 1794. Eighty or a hundred perfons died that year of the true yellow fever ; none of them were removed; but to thefe was limited the operation of the peftilential principles, local and general; and no epidemic enfoed. In New-London a cafe occurred in 1795 ; and in 1796 fev- eral cafes of the fame difeafe ; but no epidemic, altho no remo- val of the fick took place. *95 In Providence, fporadic cafes have occurred almoft every yejrf, with fymptoms of the infeaious yellow fever. In 1791, in June, died two daughters of a widow, in the center of the town. They vomited bilious matter, and their bodies were yel- low, with livid and purple fpots. Other cafes occurred the feme year ; one cafe in 1792, and a number in 1793, 4 and 5 ; cafes which could not poflibly have originated from foreign four- ces. Some of them appeared to be infeaious, as that of the young women firft mentioned, the firft being taken on the 4th of June and dying on the 7th ; the fecond being feized on the 9th, and dying on the twelfth. Yet no epidemic followed ; and had thefe patients been removed to a diftant hofpital, the fafety of the town would have been afcribed to that removal, and the falutary effea of health laws would, by Mead's followers, have been trumpeted over the country, and what is worfe, would have been recorded as an important fea, which would hereafter miflead pofterity. Nothing is more dangerous than to build a theory, or to eftab- lifh a general principle on a few detached feas, inaccurately ftated, and ill-underftood. With regard to the cafe of Rome ftated by Mead, it muft be obferved, that the difeafe had, in the preceding year, killed 10,000 of its inhabitants, and in the kingdom of Naples 400,000. The difeafe had probably finifhed its courfe in that region, and the few cafes in Rome in 1657, were only detached inftances, the remains of the peftilential caufe ; fuch as occurred in London in 1666, after the fatal plague of the preceding year. It is by no means probable that the difeafe, if negfeaed, would have become epidemic. But we have ftronger ground to oppofe the idea of the Col- lege of Phyficians, relative to the effea of health laws. Nu- merous examples are on record, in which the full force of the beft regulations to prevent peftilence, has been applied in vain ; and fince the publication of the memorial of the College, from which this idea is taken, Philadelphia has witneffed the futility of fuch regulations, in two melancholy inftances. In 1636, the law to prevent infeaion was rigoroufly executed in Londoa j the fick were confined, fufpeaed families were fe- 196 queftered; but all to no purpofe ; the difeafe fpread, the legal rcftriaions were then taken off, and no ill effea followed ; the diftemper fpread no fafter than before. '" In 1665, the fame regulations were tried in vain ; and fo was the law, prohibiting the importation of goods from Holland. The approach of peflilence towards Dantzick in 1708, in which year it appeared at Thorn, alarmed the magiftrates of the former city, and every poflible precaution was ufed to prevent its reaching Dantzick. Commerce and communication with in- feaed and fufpeaed place6 were forbidden ; no forts of merchan- dizej efpecially thofe which are moft apt to retain infeaion, "Were permitted to enter the city from fuch infeaed places ; all ftrangers and travellers were ftrialy examined, and none fuffer- ed to enter the city, without fufficient proof of coming from healthy places ; all the inhabitants were cautioned not to hold correfpondence with infeaed places, nor to harbor thofe who came from them. Thefe and other regulations were enjoined by an edia in July 1708. Yet all to no purpofe; the plague appeared at Dantzick, the next fpring. Baddam's Memoirs, vol. 6. p. 6: This is a rCrfiarkable inftanCe Of the futility of human regu- lations, when oppofed to the laws of the phyfical world. The people of Dantzick, had they been acquainted with the princi- ples of peftilence, might have forefeen in 1708, the probability of the inefficacy of their regulations. The ftate of the air in the produaion of millions of fpiders, and the increafing mortal- ity in the city, indicated the exiftence of a ftate of the air, unfriendly to health, which was increafing and only required a little more virulence to generate the evil, which they ignorantly fuppofed muft come in fick bodies, goods or old clothes ; and which they were idly combatting on that miftaken principle. It has already been ftated that the rigorous execution of health laws at Marfeilles in 1720, proved utterly fruklefs. The plague which defolated Naples in 1656 was faid to be introduced into that city by foldiers from Sardinia, where it ra- ged the preceding year. Yet the Viceroy, Count Caftrillo had prohibited all intercourfe with Sardinia. After the difeafe ap- peared which was firft in the form of a malignant fever, without w glandular tumors, all poflible means were ufed to prevent iti fpreading, but to no purpofe. The confidence in modern health laws, is like the refpea which the ancient Egyptians paid to the bird, Ibis, which, they fuppofed, averted the plague by deftroying the flying ferpents that the hot Lybian winds brought into the country. Cicero de Nat. Deor. lib. I. 36. The Egyptians were like all modern nations—unwilling to believe the plague generated at home—they afcribed it to infec- tion brought by flying ferpents, as the moderns afcribe it to old clothes, bales of goods and infeaed fhips. They miftook the caufe, adored Ibis, as the moderns do, quarantine, and with the fame ill fuccefs. But we need not ftep off Of our own territories to find evi- dence of the inefficacy of health laws, when oppofed to the op- eration of the laws of nature. No expedient has been left un- tried to ward off the calamity of peftilence, but without any vifible effea. The feverity of the affiiaion in Philadelphia, in former years, liad rendered the magiftracy of the city extremely careful to guard againft importation in 1798. The moft rigid quarantine was exaaed—ventilators of the beft conftruaion em- ployed—the veffels were waflied, fumigated, white-wafhed with lime, and every praaicable mode of purification adopted. Not a veffel was fuffered to approach the city, without fatisfaaory evidence of the healthy ftate of the people, and the falubrity of the veffel and cargo. See the letter from Hillary Baker, Efq. mayor of the city, to the mayor of Baltimore, dated Auguft 13th, 1798. Alas! all to no purpofe ! The ravages of the difeafe are well known. If, fays the late worthy mayor, the difeafe has eluded the health officers, I fhall defpair of future fuccefs, unlefs the Weft- India* commerce fhall be prohibited in the fummer months, and , magazines eftablifhed below for receiving the cargoes. Similar provifions in other ports have been eftablifhed with no better fuccefs. The health laws at New-York, fo far as appears, ivere as well executed in 1795, 96 and 98, when the fever-was epidemic, as in 1794 and 97 when it was not. No vifible good .effeas are to be difcoyered in guarding againft an epidemic j the i$8 utiUty of cleanfing veffels therefore is limited to guarding againft the operation of infeaion, upon a few perfons who may enter them, with foul air on board. Public health, fo far as can be difcovered, has never been fecured by thofe regulations. What feems to place this point beyond queftion is, that, for thirty years preceding 1792, no peftilential fever ever fpread in America, from the ten thoufand infeaed feamen and paffengers, which ar- rived in the country from the Weft-Indies, and during which time, in moft places, not the leaft precaution was ever ufed to guard againft it ; yet fince 1792, that is, under a ftate of air, generating various epidemics, the peftilential fever has appeared in fporadic cafes, every year and in almoft every town in Amer- ica, and has raged as an epidemic in moft of our large towns, in oppofition to the utmoft efforts of human fkill. I am perfuade4f the conclufions from thefe feas amount to demonftrative evidence, that infeaion is not the principal, or caufe fine qua non, of this terrible calamity. The application of quarantine laws to our epidemic peftilential fever, is juft as ufelefs, as the order of the Sultan, Achmet L in the wafting plague of 1613, for tranfporting all the cats in Conftantinople to the ifland of Scutari. The Jewifh phyficians teld the Emperor, that the plague was occafioned by the cats, and the poor cats were difpatched into exile. Yet this did not reftrain the plague. k People have been forever miftaking the caufe of the plague. In the firft centuries of the chriftian era, when difputes ran high between Chriftians and Pagans, thefe feas mutually charged the plague each to the other. In 1349, the Germans afcribed the, plague to the Jews, and maflacred great numbers of that race. In Paris, during a plague, many proteftant heretics were facrificed, for bringing the calamity upon that city. And a propofition has been made in America to flop all intercourfe with the Weft-In- dies and the Mediterranean, during the fummer months ! Af- toniming blindnefs! But, it will be afked, fhall we have no health laws ? I anfwer, by all means. Their utility is obvious on many occafions. Thus when an infeaed fleet arrives in a port, the town is in eminent i99 danger, of what may be called a jail fever on a great fealc. The quantity and virulence of infeaion thus imported, have produced deftruaive confequences, as at Breft in 1757, where were lan- ded in November and placed in hofpitals, about five thoufand difeafed feamen and troops from fhips, moftly out of De la Mot- te's fleet, from Louifburg, with a malignant fever on board;! The effea was that ten thoufand men died, in the hofpitals, the fucceeding winter, and many of the inhabitants of Breft. But it will be remarked, that this infeaious difeafe did not become an epidemic in Breft ; it fpread only by infeaion; and as foon as that was diflipated, the difeafe difappeared. It raged in winter and fobfided in fpring. This is an important diftinaion, always to be obferved by thofe who guard the public health—an epidemic pef- tilence begins when the feafon or the ftate of air favors it, and rages without control, againft all human efforts ; the common air becomes tainted, fo as to produce the difeafe, without the infec- ting principle from bodies or clothes, and the difeafes fubfide on- ly at the command of the feafons and the elements. Againft fuch, no legal provifions are or can be of any avail, and fuch is ufually the yellow fever of our country. But difeafes propagated only by infection, like the jail and fhip fever, never put on the form of an epidemic. They rage in crouded prifons and fhips, where they are generated,; and when multitudes are crouded into hofpitals, they carry the evil with them ; and all perfons, coming within reach of the infeaion, are liable to fuffer. In this manner, Breft loft many of her in- habitants ; a town in America is faid to have done the fame, from the yellow fever,d imported in Sir Francis Wheeler's fleets as already related. But in fuch cafes, the infeaing difeafe re- quires contaa or near approach to aid its propagation ; and does not affume the complexion of an epidemic. The two fpecies of difeafe are as diftinguifhable as light from darknefs. Thus, at the Black aflizes in Oxford, in 1577, a malignant or jail fever of a lingular kind, was produced fuddenly—almoft all the court and fpeaators were feized—many died—but no epi- demic followed in Oxford j and in this inftance, the effea was fo fudden, that the human body did not generate infeaion. 200 So alfo at the Old Bailey, not many years paft, a few prifon- ers, entering the court from a dirty jail, without changing their drefs, infeaed a large number of perfons who died; but no epi- Mernic followed—the infeaion was foon diflipated, and there was an end of the difeafe. With our peftilential fever, this is not the cafe, nor with any epidemic plague that ever exifted. Remove the fick, cleanfe the houfes and clothes, do whatever human art and labor is compe- tent to effea, all will not avail—cafes fpring up in every quarter, and the difeafe takes its courfe. So it was in Candia in 1592, as related from Thuanus, un- der that year. As foon as the plague appeared, all the fick and all the fufpeaed were removed from the city ; but to no purpofe ; It raged till July—then abated without any human means and re- vived again in Oaober. Thus fays the author of Traite de la pefte, " Univerfal clean- tings have proved ufelefs ; the plague has ravaged places after ev- ery precaution ; and after negligence it has entirely ceafed, as in Naples." Such are the feas ; and hence the neceflity of diftinguifhiflg^ Carefully between epidemic peftilence, proceeding principally from general caufes in the elements, and marked by other epidemic difeafes, by the failure of vegetable produaions and by the fick- nefe", or death of cattle, fifh and other animals—and difeafes merely infetlious, generated by artificial means, which may be communicated, which may happen in jails, fhips and camps, in the heakhieft ftate of the elements, and which ceafe, as foon as the infeaion can be diflipated by purifications and frefh air. Without this diftinaion, the merit of legiflative and police-regu- lations, can never be duly appreciated. Such regulati6ns, ap- plied to epidemics, as they continually are, prove totally futile— applied to difeafes of mere infeaion and of fpecific contagion, as jail fever and fmall pox, they may be and often are the means of preferving multitudes of lives. It is important therefore that health laws thould be judicioufly framed and ftrialy executed, becaufe there may be cafes in which * public health will be preferyed by them ; altho they neyer cajr 201 reach the caufe or. prevent the ravages of epidemics, which orig- inate where they exift. -With refpea to merchant-men, health-laws may alfo be of feme ufe, in preferving the lives of feamen, and of perfons con- cerned in the veffels. Sick men may generate a fmall degree of infeaion ; but on board of merchant-men, the number of fea- men is too fmafttto infea a fliip, fo as to endanger public health* 1 Ufllefs -fhamefully negfeaed. The moft danger from merchant-men is from the foul air gener rated, on long voyages and in hot feafons, from perifhable and i fermenting fubftances. From fuch vitiated air, deprived of its yital principle, great danger may arife to the perfons who firft open and enter the holds ; and perhaps to a neighborhood. It is of great confequence therefore to ufe ventilators freely on board of veffels, freighted with perifhable articles j and to have them effeaually cleanfed, before they are fuffered to approach pur wharves. ...ButI am not convinced that the air of fuch veffels ever yet originated an epidemic fever. It appears to me, that the Acad- emy of Medicine in Philadelphia, lay more ftrefs on this caufe, B than it deferves. The fphere of the operation of fuch a fmall morbid caufe, cannot be extenfive ; and all the foul air of the largeft veffel muft be fo attenuated by diffufion, as not to pro- duce deleterious effeas, at any great diftance. It may be inju- rious to a fmall neighborhood ; but I do not conceive it poflible, that the noxious air of a few fquare yards, can impregnate the whole atmofphere of a city ; and as to infeaion from the fick, I have repeatedly proved, that this can never produce an epi- demic. I will admit the bare poffiblllty, that imported infeaion \ may enkindle the flame of peftilence, in a place fitted for it by local caufes, where no peftilence would appear without a fpark from infeaion. This is as much as I can admit to be poflible, and more t\vsv I believe ; after a more minute and careful invefti- gation of feas probably, than was ever before made in America. Moft of the cafes I can find, where accurate accounts are pre- ferved, of fuppofed importation or communication of autumnal difeafes, fail utterly of proofs to fupport common opinion ; and Vol, II. B b 202 many of them are incontrovertibly pfoved to have had their ori- gin in the places where they have exifted. - It is eafy, I aver, todiftinguifh, in every cafe, the nature of peftilence ; that if, whether it is an epidemic, proceeding from ra-ftate of the elements, or a difeafe generated folely by foul air,. artificially colkaed. In a few weeks, if not a few days, a dif- eafe will fhow whether it proceeds from infeaion only or from a general elemental fource ; and when it appears to proceed from the elements, men may juft as well attempt to fave the cats, the wild animals or the fifh in the ocean from the effeas of that principle, as their own fpecies, by laws enjoining quarantine and purification of fhips. The fame caufe that deftroys the cats or the fifh in one cafe, deftroys human life in the other ; and that caufe exifts in the elements ; it is at home ; quarantine laws do not reach it. An epidemic difeafe maybe diflinguifhed from a difeafe pro- ceeding from infeaion or fpecific contagion, by the following cir- cumftances. i ft. An epidemic peftilence is preceded by influenza, affect tions of the throat, Or acute and malignant fevers. 2d. An epidemic predominates over other difeafes; totally abforbing them or compelling them to affume its charaaeriftic fymptoms. This laft circumftance is decifive of the character of the difeafe. A difeafe propagated by contagion or infeaion only is not thus diftinguifhed. It has no precurfors, it extends and fpreads only by contaa or near approach ; and has no effea on the difeafes in its vicinity. The fmall pox or jail fever, depending on mere in- feaion, never expel a dyfentery or intermitting fever. In every poflible cafe, a plague that baniflies other difeafes, as I believe it always does, is an epidemic generated in the place where it exifts ; for it is not poflible that this expulfion of odier difeafes, could take place, unlefs the epidemic depended folely on the elements. Simple infeaion would not change the fymp- toms of another difeafe, even in the next houfe, much lefs in all parts of a city. To fhow how little an epidemic depends on infeaion, let us advert to feas. In all the eaftern countries, the plague is fuffer- ed to take its own courfe without reftraint. There are no regu- lations to control its progrefs, or prevent its return. Its begin- ning is ufually gradual; a few die the firft year ; the proper fea- fon fufpends its progrefs j the next year it is more general, and often, the third year is the moft fatal. It is remarkable, that after its moft extenfive effeas, it abates and fuddenly difappears. In London, the malignant precurfors of the plague of 1665, appeared as early as 1661 ; butnofoon- er had its crifis paffed, than in a few months, it was totally ex- tinguifhed. The fame happened at Aleppo in 176.2, and fuch is ufually the fea. Let any man fuppofe the difeafe to be propagated wholly or moflly by infeaion, and attend to the confequences. In Alep- po, fays Ruffel, died 500, in 1760; in 1761, died 7000, and in 1762, 11,000. On the principle of infeaion then, fome fick man or a bundle of old clothes, firft fpreads the difeafe, fo as to deftroy 500 lives—the infeaion of 500, deftroys 7000 lives, the infeaion of 7000. deftroys 11,000 lives ; and the next year, the infeaion of 11,000 deftroys—none at all ! In London, a few bales of cotton, fmuggled in,to the. city from Holland, in 1664, communicated infeaion that deftroyed 68,000 lives ; the infeaion from this immenfe number proves fatal, the next year, to 1900 only ; and thefe, the year following, infea only 35 ! If infeaion has much con- cern in propagating that difeafe, its operation certainly defeats all arithmetical calculation of its phyfical powers ! The whole theory of infeaion, to which Mead has given fo much celebrity, and which is maintained by many phyficians in this country, is abfurd and ridiculous from firft to laft ; leading legislators, magiftrates and citizens aftray from the truth, produ- cing moft ferious inconveniences to commerce, and preventing the adoption of the only means of mitigating the peftilence to which our cities are expofed. In Turkey and Egypt no pains are taken to cleanfe houfes or clothes after a plague. No fooner has a great plague ceafed, which has cut off" 300,000 people in Conftantinople or Cako, than the infeaed houfes are filled by other people, who repjace the dead, ufe the furniture and the bedding on which the infeaed fce>4 had died ; or the old clothes are fent to auaion and purchafed by Jews, who retail them out for ufe, uncleanfed ; and yet amidft all this mafs of concentrated infeaion, no perfon has the plague, or if a fporadic cafe occurs here and there, no epidemic enfues, for two, three or four years, perhaps longer ; then all at onct, when the infeaion muft Heceffarily be deftroyed, by the aaion of air and water, the difeafe breaks out again, and becomes epidemic. Then fome arrival from an infeaed place is hunted out, and the calamity is charged to the account of fome poor fick feaman, or his clothes ! The infeaion of half a million of people, produ- ces no plague in one year ; but in another, the invifible fomes of a piece of cloth, or the breath of a tingle man is fufficient to fpread defolation over a great city, or a kingdom !* Such are the abfurdkies of the modern notions about the plague, which adorn this fplendid era of philofophy and fcience !— Of the nature of the infeaing principle in difeafes, we know very little ; and even its effeas are not always comprehenfible. We obferve differences alfo in the operation of the principle, which we cannot explain. Why the fmall-pox fhould be com- municated, under all circumftances ; the plague only under cer- tain circumftances, is a myftery not yet unfolded. It is fuppof-. ed, that the difeafed body difcharges certain fine poifonous parti- cles, which are fufpended and diffufed in the air, and being im- bibed by the pores of the flcin, and with the breath, excite the, fame fpecies of diftemper in a healthy body. Thefe effluvia generally efeape our fight and very often our other fenfes ; but they may be concentrated in fuch quantities, as to be very ob- noxious to the olfeaory organs, and even to excite fudden nau- fea in the ftomach. But why the effluvia from the fmall-pox, anginas and the mea- fles fhould be independent of heat and cold ; and thofe of dyf- entery, plague, and other typhus fevers, fubjea to be excited * Hodges informs us, that after the plague in London, in 1665, peo- ple returned into houfes not cleanfed, and even flcpt in beds on which the infeaed had died, without fear or injury. This is not at all frrangc. Unlefs the effluvia from the fick have been clofely conrined and are greatly condenfed, they will not affect a well perfon ; and indeed it is a difficult thing to prcfcrve the morbid matter, in fufikier.: quantity to communicate difeafe in cold weather. 405 into aaiOn by the one, and to be deftroyed by the other, is a phenomenon never yet explained. We may fay the particles if- luing from the former clafs, are more fubtle, volatile, and pene- trating ; but this is all cdnjeaure. Certain it is, that the poifon of fmall pox, angina and meafles, is of a more diftina, fpecific kind, than that of the plague, lefs conneaed, in its operation, with putrid exhalations from other bodies, and lefs fufceptible of grades in its powers. So fer as I am able to comprehend the nature of the infeaion of plague and other autumnal difeafes, pafling under the popular tame of putrid, it appears to confift of a fpecies of air, which is one of the elementary parts of all vegetable and animal fub- flances. It may be what Dr. Mitchell denominates,*.the feptie acid ; that fluid which is difcharged from flefh in the procets of putrefaaion. It may be fome other fpecies ; but it is very evi- dent, from all its effeas, that it operates, in producing difeafe, no otherwife than all the morbid exhalations extricated from ev- ery fpecies of vegetable and animal fubftances in the putrefac- tive procefs. In all or moft of fuch fubftances, there is, it is well known, a fpecies of air or acid matter, which, when in a form detached from other fubftances, is highly noxious to health. To this fluid, or feptie acid, evolved from vegetables" in a ftate of natural putrefaaion, and floating in an aerial form, is afcribed the whole clafs of bilious fevers, which prevail near marfhes. Hence, the effluvia from a perfon laboring under the plague, are fufceptible of all degrees of concentration, and in proportion to their concentration, will be their violence, and certainty of effea, when they attach themfelves to a healthy body. In this refpea, the infeaion of the plague differs moft cflentially from that of the fmall pox. The matter of contagion in the fmall pox, however fmall, is fufficient to communicate the difeafe ; and it is cuftomary for phyficians to wipe clean the point of a lan- cet, dipped in variolous matter, before it is inferted in the flcin, for the purpofe of inoculation. It is alfo proved by experi- ments that the quantity of infeaion introduced by inoculation, whether more or lefs, makes no material difference in the num- ber of puftles, or violence of the difeafe. 2o6 . But if the plague, the operation of infeaion is very different. This difeafe, if light, produces no infeaion, or very little— more violent cafes appear to be more apt to be communicated—, and in great plagues, the infeaion h vifibly augmented. Yet in moft peftilences, an inftantaneous expofure to the effluvia from the fick will rarely produce any effea, as in the cafe of fmall pox and meafles. It ufually requires a perfon to be a confiderable time in the room with the fick, in the plague, to receive poifon- O.us air fufficient to excite difeafe ; and more generally, it is ndt communicated, without handling the fick or imbibing his breath. In many cafes, all this expofure for weeks and months together, will excite no difeafe. Hence Ruffel reprefents the plague, as of different degrees of malignity and not always infeaious. Hence the propriety of clofe and indefatigable attention, in pef- tilence, to every article of cleanlinefs ; for by this means, the quantity of infeaion is reduced, and the danger diminifhed, from a high degree down to nothing. Not fo, in fmall-pox and meafles, the contagion of which regards not filth or cleanlinefs. The infeaion of the plague, dyfentery and the like feems therefore, to be nothing more than an accefs of noxious matter, to the local caufes, morbid exhalations. The noxious air of filthy ftreets, docks and tenements, are fecondary and augmenting caufes of the plague ; when the difeafe appears, the effluvia from the difeafed ftill augment thefe other local caufes. Thus when a certain ftate of air, in a city generally, will produce a malig- nant fever, and perfons are expofed to it by walking in the ftreets, a fkk perfon, confined in a clofe room, will foon fill that room with exhalations from his lungs and pores, which will render that room more dangerous to a perfon in health, than the open ftreet. This feems to be the amount of the infeaion of plague and other autumnal difeafes. Thus alfo in a violent plague, the common air of the ftreets becomes fo highly infeaed, that perfons attending the fick can- not poffibly determin whether they take the difeafe from the common atmofphere, or from their intercourfe with infeaed per- fons. The only cafes which afford certainty ia this refpea, are, when the difeafed are removed into the pure air of the country, 207 and nurfes and vifitors, who have breathed no peftilential air in the city, are taken ill, in a few days after fuch intercourfe with the fick. Thefe would be clearly the produce of infeaion. But thefe cafes rarely occur. It has already been obferved that the worft cafes of peftilence removed into the country, feldom infea the attendants. This ftiows how little apprehenfion ought to be excited by mere' infeaion, and how ill-founded are the alarms in the country, about the fpreading of the yellow fever; alarms that often occafion a negfea of difeafed fugitives from the city. People in the country have little to fear from infeaion, if the fick are kept in airy rooms and cleanly ; they ought not to abandon the fick; for the duties of humanity are not incompat- ible with their fafety. It is the infeaed ground, if I may fo call it, the local atmofphere of peftilence which is to be dreaded, and efpecially by ftrangers. During its prevalence, in a city or town, the air of the place is rank poifon to perfons, accuf- tomed to good air. The preceding feas and diftbaions enable us to form a juft ef- timate of the importance of health laws. In nine cafes of ten, in which quarantine is enjoined, human efforts are oppofed to the great laws of nature, and are therefore ufelefs. In all cafes, where the air of a country exhibits evidences of a peftilential conftitution, in an increafe of the number and violence of the fymp- toms of common difeafes ; in the produaion of certain epidem- ics, as catarrh, anginas, meafles, petechial fevers and the like ; in the death of fifh or the unufual difeafes of cattle and other an- imals ; in the produaion of infeas, uncommon in fize, in kind or numbers ; and other remarkable phenomena, before mention- ed ; in all fuch cafes, the peftilence which invades man will be found to arife folely from the uncontrollable laws of the elements ; and quarantine will be utterly unavailing to guard cities againft its introduaion and ravages. The remedy is not applied to the fource of the difeafe. Hence the efforts of the police in London in the laft century, and of Dantzick and Marfeilles in this, were entirely ufelefs ; and hence the failure of all health laws to fate eur cities from the late epidemics. 2o8 t Satisfied a^ I am of this truth, I would not lay afide the appli* cation of thefe laws. The bare poflibility of faying thej lives of a few . individuals, and efpecially of difeafed feamen, is a good reafon for cleanfing fhips after long voyages, and qf purifying their cargoes, when in a bad ftate. But what I contend for, is, that ye.muft notexpea the beft health laws,moft rigoroufly executed, will ever be -iuccefsfulin guarding cities againft epidemic peftilence. In our reliance on fuch regulations, we expofe ourfelves to per- petual difappointment; we expofe the lives of citizens ; we over- look the true caufes of the evil, and negfea the only means of preventing or mitigating its effeas. Further, the opinion of the fpecific contagion of the plague has originated many, not only ufelefs, but barbarous regulations, Such is the praaice of confining the fick to clofe houfes ; and ftill more, of confining the citizens of an infeaed town within its limits, by an armed force—which I am informed has been done in Europe. In Marfeilles, the firft perfons feized were con- fined to .their houfes by the point of the bayonet. . An ignorance of the nature of a difeafe and its degree of dan- ger, may be pardonable in a prince or the legiflators of a free ftate. But there is a point, beyond which ignorance in medical profef- fors, becomes a crime. No fcience is neceffary however to con- vince any man, that moft peftilences, proceed only from the de- ranged ftate of the elements, aided by the morbid exhalations of cities; This is a fact that may be known to a certainty by vety little reading and obfervation. It was well known in paft ages, when men were more governed by-obfervation, than by t'Hebfles and erroneous reafoning. Mead's attempts to prove the- fpecific contagion of plague, aided by his popularity, had a moft furprifirig fuccefs ; his treatife was received as a ftandard of truth ; it every'where fufpended' enquiries and checked a fpirit of inveftigation, which might have drffipated error ; it was the ba^' frs'-of the prtfent laws of quarantine5, which-are apnlied, in'thbff-' fsmd's of "Cafes; "where they are as improper and-as little wanted; ZS if applied to-pre'vent ah epidemic pleurify, or headache/ em- barraffing commerce, wifhout the fhadow'of nec«flity. •'■ ButKhefe are not the worft effeas. The- erroneous fyftem of fpecific cion- 20$ tagion, has miflead mankind into a fatal fecurity, on the fubject of the local caufes of difeafes. Suppofing the laws competent to guard public health, men have not attended to the beft modes of conftruaing houfes and cities, and to the means of watering and cleanfing them—means fty which all the flighter peftilences might be avoided,and the more fevere ones, greatly mitigated. Hence I am perfuaded, that the received theory of fpecific contagion is the direa caufe of moft of the fatal plagues that now feourge civ- ilized Europe and America. For it will be obferved, that pef- tilence has always been the peculiar curfe of populous cities. Of about two hundred general plagues, recorded in hiftory, a few only have been fo violent as to fpread over countries into villages and farm houfes ; almoft all have been limited to large towns, evi- dently demonftrating that they would never have affeaed man- kind, without the influence of the impure air generated in thofe places. This is a truth, as unqueftionable as it is important; and on a conviaion of this hangs the fafety of men from that dreadful calamity. Had Mead, and other eminent phyficians taken the fame pains to lead mankind into truth, as into error, we fhould long ago have introduced improvements into the ar- rangement and ftruaure of our cities, which would have fecured, our citizens from nine tenths of the infeaious difeafes, by which they have been alarmed and diftreffed. At the fame time, had men underftood the common operation of infeaion, which may be made obvious to the moft ordinary minds, merchants would not, at this day, have been harraffed with the neceflity of performing quarantine, to guard againft epi- demic difeafes. We fhould not have feen a fliip from the Weft- Indies condemned to the flames, in a Britifh port, becaufe the had loft her crew by the yellow fever; nor merchantmen from an American port obliged to ride quarantine in the Britifh chan- nel, becaufe that difeafe prevailed in this country. Phyficians, had they not been blinded by fyftem, and taken opinions for granted, without enquiry into the grounds on which they reft, would have known before this, that the yellow fever will not fpread in England, Scotland or Ireland. It never fhows itfelf Vol. II, C c 210 in America, without a much greater degree of heat, than the ordinary fummer temperature of thofe countries. The heat in thofe latitudes rarely exceeds, for a few hours, in a tingle day, 75 or at moft 78 degrees by Farenheit. BHt no epidemic yel- ldw fever is ever generated, in our climate, with that degree of heat. In general, we never fee cafes of that difeafe in America, until we have "had a period of heat riling, for a confiderable time, to 85 deg. or higher. In any feafon of ordinary temperature, the yellow fever, in the Britifh kingdoms, and other parallels of latitude, introduced from abroad by feamen or others from war- mer climates, would immediately fubfide and be extinguifhed, without any human efforts. The cafes of malignant fever in England, which turn the body yellow, and which fometimes oc- cur, as mentioned by Lind, are generated about marfhes, in hof- pitals, camps, fhips and prifons. An epidemic yellow fever, like that which prevails in America, was never known in Eng- land, and probably cannot exift in the climate. The quarantine enjoined on veffels from the Weft-Indies and United States, is utterly ufelefs in guarding that country from this peftilence in the form of an epidemic. It may be faid, in anfwei to thefe remarks, that the yellow fe- ver and plague are effentialry the fame difeafe; the plague has of- ten raged in Great Britain, and therefore the climate may not re- fill the prevalence of the yellow fever. But if the plague has raged in Great Britain, which is admit- ted, it muft have arifen from the unhealthy ftate of the elements, which may exift in any latitude, or from very lingular feafons, aided by moft powerful local caufes, as in London before it was burnt. I fay the yellow fever will not fpread in England, in the ordinary ftate of the elements, and the ordinary temperature of the fummer. If peftilence ever invades cool northerly countries, it muft always proceed principally from diforders in the elements and feafons. The ordinary caufes, in temperate or cool cli- mates, have but little influence in generating peftilence. Hence in common feafons, in England, no plague, bilious or inguinal, could be fpread, unlefs in a crouded jail, camp, or dirty, con- fined alley in a city. If the phyficians in England obferve the 4U general ftate of health to be good ; no epidemics, with unufuaji fymptoms, prevailing ; no uncommon numbers of infeas ; or difeafes among cattle, or other fymptoms of a morbid ftate of the elements, it is no more in the power of man to render the plague epidemic in that country, than k is the pleurify or quin- fey. I challenge all the faculty in Europe, to mention an in- ftance, in which plague has ever prevailed, without fuch phe- nomena. Betides, it feems to be probable, that more heat is neceffary to generate and to propagate the bilious, than the glandular plague. My reafons for this opinion, are, that the glandular plague appears in fpring much earlier than the bilious. It often appears in the northern parts of Europe, as early as March and often in May, when the weather is yet cool. But the bilious plague of our climate has not fhowed itfelf, in fporadic cafes, till June, and then very rarely, and only in a few fcattered cafes of a lefs malignant type, than at a later feafon. To this remark, I have heard of only one exception. Generally, the difeafe does not appear till we have experienced fome days of our hotteft weather, and not till the laft week in July, except in a few cafes as before mentioned. It does not become formidable, as an epi- demic, till the tenth or twentieth of Auguft. This difference feems to depend on the following circum- ftances. The glandular plague of Europe, Afia and Africa, when it breaks out in the northern latitudes, as on the Baltic or in Great Britain, feems to be more eflentially and principally the produa of a defeaive ftate of the elements, joined to human ex- halations in large .cities ; both which caufes are lefs dependent on heat, than the morbid exhalations of the vegetable world, which feem to give to our American plague its peculiar charac- ter, and to be a powerful caufe of the diftemper. I amjurther confirmed in this opinion, by this circumftance. A diftinaion between the bilious fevers of our cities, and of our marjhy grounds on rivers, is obferved to exift, in perfea analogy with the foregoing diftinaion between our bilious plague and the glan- dular plague. The mortal fevers, about marfhes in the interior of our country, are lefs infeaious, than the peftilential fever* of 212 #iH> cities, altho they ate at times as fatal, and are charaaerized by a yellow fkin. Thefe feem then to proceed wholly from veg- etable exhalations. The fevers of our cities approach nearer to the plague of the eaft, becaufe they proceed both from animal and vegetable exhalations, but the vegetable effluvia have a more predominating influence here, than in countries which are dry or better cultivated. Hence the mortal bilious fevers of our interi- or country evidently form a link in the feries of gradation, be- tween the common remittents, and the yellow fever of our cities; juft as the yellow fever con ftitutes a grade between our river or lake fevers, and the Levant plague. The order of bilious fevers then (lands thus in conneaion with their caufes :— In healthy periods. Common intermittents, "5 folely from marfh effluvia, and ordi- rernittents— 3 nary caufes. In peflilential periods, undef the operation of elemental caufes. Intermittents, 7 of a worfe type, from marfh effluvia, aided by remittents— J a general caufe. Bilious plague of the country, 7 folely from marfh exhalations, near lakes and rivers— 3 with the general caufe. Bilious plague of A- 7 from the joint operation of vegetable and merican cities— 3 animal effluvia, with the elemental caufe. Inguinal plague *^ principally from animal exhalations, with the of the eaft— 5 elemental caufe. In this gradation of difeafes, there is a regular progreffion of fymptoms. Intermittents and remittents exhibit a yellow fkin, more or lefs, but no infeaion worth naming—the river or lake plague, a very yellow fkin, with morbid fymptoms, but little in- feaion—the bilious plague of cities, fometimes a yellow fkin, fometimes not; and fome cafes of glandular tumors, carbuncle and petechias ; with more infeaion—the Levant plague, lefs yellownefs of the fkin, and ufually infeaion and glandular fwel- lings. Thus, in proportion as the vegetable exhalations predonv 213 mate, in the fcale of exciting caufes, there is more yellowneft of the fkin, lefs infeaion, and lefs frequent affeaions of the glands—in proportion, as the animal exhalations abound, as the caufe, the yellownefs declines, and the affeaions of the glands multiply, with augmented infeaion. It is the remark of the celebrated Zimmerman, that " exha- lations from marfhes do not feem to be fo noxious in cold, as in hot countries ; yet malignant fevers occur even in Finland. In Germany thefe exhalations produce tertians; in Hungary, pe> techial fevers ; in Italy, hemitritaea ; in Egypt and Ethiopia, pef- tilential fevers." On Phyfic, p. 131. It is therefore probable that a greater degree of heat, than the ordinary temperature of Great Britain, is neceffary to generate the peftilential fever of our cities. And as no degree of infec- tion ever yet accumulated on board of a merchantman, can cre- ate a peftilential atmofphere, fufficient to generate an epidemic, the fears of the Englifh refpeaing fuch veffels from the United States or the Weft-Indies, are utterly groundlefs. The marfh .fevers of England, Scotland and of other cool climates, are ,of an inferior grade. Such are the autumnal fevers near the Fenn's of Lincoln, Ely and Cambridge. In Torbat, in Scotland, a putrid fever fometimes prevails, and after death, the body turns yellow; this may be afcribed to certain natural locks or ponds which fometimes dry up in fummer. Sinclair's Scot. vol. 6. 418, 428. But thefe difeafes, tho doubtlefs the fame in fpecies, fall great- ly thort of the violence of our peftilential yellow fever, which never did and probably never will prevail in that climate. &i4 SECTION XVII. Of the means of preventing or mitigating peflilential difeafes. r u"i X HE firft ftep towards an effeaual remedy for an evil, is to afcertain its nature and caufe, fo far as they can be underftood by effeas. Primary caufes are above the reach of man ; proxi- mate caufes, may be fo far inveftigated, in moft things, as to an- fwer all the purpofes of mankind. It has been proved, in the preceding pages, and every day's obfervation confirms the fea, that one influential caufe of epi- demic difeafes, muft exift in the elements, independent of all human control. In the produaion of epidemic catarrh or influ- enza, for inftance, no human or artificial means appear to have any fhare of influence. In the meafles, artificial caufes fome- tirnes modify the fymptoms, but have no great fhare in its pro- duaion or propagation. A fimilar remark will apply to every foecies of angina. The fmall-pox is alfo modified in its force and fymptoms by many local circumftances j and its propagation is chiefly by means of contagion ; but this difeafe alfo is fome- times, tho rarely, generated in particular bodies without conta- gion. The appearance of thofe difeafes in the form of epidem- ics, excepting the fmall-pox which may arife from contagion, always indicates a peftilential conftitution of air ; and during this conftitution, ordinary or annual difeafes, which depend on feafon or local caufes, affume more violent fymptoms. Autumnal difeafes of the annual or ordinary kind, tho ren- dered more violent, fatal and extenfive, by a peftilential ftate of air, are however generated by fubordinate caufes, moft of which are within the power of man. The dyfentery depends partly on feafon, partly on fituation, as to pure air, and partly perhaps on the imperfeaion of autumnal fruits. Sometimes it arifes in *'5 camps from bad diet, or want of fhelter from the weather ; and when k once exifts, is more or lefs propagated by infeaion. But this difeafe is rendered more malignant, by elemental caufes. Ordinary bilious fevers of all grades are produced ufually by miafmata or morbid exhalations from low, damp, marfhy grounds; where vegetables, in the hot feafon, are in a ftate of rapid pu- trefaaion. Thefe fevers occur annually, and with a violence of fymptoms proportioned to the extent and force of the morbid caufe. The origin and phenomena of all this defcription of difeafes are fo well known, as to render any obfervations of mine, unneceffary. The plague, glandular and bilious, feems to be nearly allied in its fymptoms, to the ordinary bilious remittent. The point feems not altogether fettled, whether the contagious yellow fe- ver, as it is ufually called, and the common fporadic yellow fever of the Weft-Indies, and the bilious remittent, are different grades of one fpecies of difeafe ; or whether they are of diftina fpecies. On this point however, the late epidemics have furnifhed our fcientific men with proofs that appear to me to decide the queftion, in favor of the identity of the fpecies. The evidence arifing from the difeafe in Baltimore is alone fufficient to decide it, as far as it regards the yellow fever and the remitting ; and the Acad- emy of Medicine in Philadelphia is a moft refpeaable authority in favor of the fame doarin. That the glandular plague of the Levant, and the bilious, in- feaious yellow fever of our country, are fpecifically the fame difeafe, I have no doubt; but they take fome different fymptoms, either from climate, or other caufes unknown. The glandular tumors are held, by moft writers on the plague, to be the char- aaeriftics of the difeafe, which alone decide its nature, and difr tinguifli it from other malignant fevers. But Diemerbroeck and all the beft authors agree that thefe external fwellings are not effential to the difeafe, and that many have the true plague without them. They are however the ufual marks of the difeafe. In our bilious peftilence, thefe fwellings are lefs common, But> tho rare, they fometimes appear, in the moft unequivocal 2l6 form of the true peftis. I faw an inftance in 1796; and they were more common in the laft epidemic. An inftance occurred, .within my knowledge, in which two auxiliary tumors appeared, and the perfon was never confined by fever. The yellownefs of the fkin has given name to the peftilence of our country; yet this is a misfortune, for it may deceive a common obferver. A yellow flcin often accompanies lower grades of bilious fevers, not peftilential; and is, by no means, effential to the infeaious yellow fever. In all our late epidemics, per- fons have died without exhibiting this color of the fkin ; and it has been lefs common the laft year, than in former years. It appears then, that the lighter the epidemic difeafe, the more common the yellownefs of the fkin; and vice verfa. This is no inconfiderable proof of the identity of the bilious and ingui- nal plague; that in proportion as the bilious plague of our cli- mate becomes violent and approaches the true plague, it lofes that yellow color of the fkin, and affumes the glandular fwellings. This I am informed is the fea, as obferved by the phyficians in New-York, the fummer paft. There are however fome differ- ences in the fymptoms of the two fpecies of plague, which it belongs to the faculty to obferve and define. It may be that the . moifture of our country, not yet cleared of its woods, and abounding with fwamps and marfhes, may occafion the differen- ces in the fymptoms. The parts of Europe, Afia and Africa where the plague moft ufoally prevails, are clear of woods, and • cultivated. Perhaps an increafe of population, and human efflu- via, with a decreafe of vegetable exhalations in America from cultivation, may in time change the form of our peftilential fever into the true inguisal plague. I have reafons for,believing fuch a change aaually took place in Rome. Some of the plagues, defcribed by Livy were obvioufly of the bilious kind, fimilar to our epidemic fever; but in later periods, the plagues in Rome are exprefsly defcribed to be, " peftis inguinaria." However this may be, the caufes of peftilence I fuppofe to be, firft fome effential alteration in the primary qualities of air and water, owing to feafons, or to the aaion of the principle of fire, the main operative agent in the earth and atmofphere; which al- 217 teration is demon ftrated by various epidemics and efpecially by ca» tanh—fecondly, the fubordinate caufes of plague, are, noxious exhalations of every kind, which diminifh the proportion of vi- tal air imbibed into the lungs. Both caufes appear to produce dif, eafe, either by exceflive excitement, inducing indlreS debility; or by reducing excitement, and inducing dlreS debility. The aerial pr elemental caufe feems to produce exceflive excitement3; for its firft effea appears in catarrh, a difeafe of ftenic or inflam- matory diathefis. Thus the prefent epidemic conftitution was preceded by influenza,of univerfal prevalence and of fevere fymp- toms. " ", Meafles, another difeafe that rarely fails to charaaerize the early ftages of a peftilential conftitution, is alfo of an inflamma- tory diathefis. The fame 13 true of the common diftina fmall- pox—-another difeafe, which, before the art of inoculation, feldom failed to rage in cities, during fuch a conftitution. Anginas are of different types ; fome of the milder kinds are .ranged-by Brown amomg ftenic difeafes ; but the angina maligna he. confiders as aftenic. Difeafes of this clafs however form a part of the effeas of a peftilential conftitution. Next to this fpecies of difeafes, may be arranged the petechial fevers, which under the names of purple, or footted, have often overfpread Europe, and rarely fail to precede the plague. Thefe are the produa of the laft ftages of a peftilential conftitution, next to the true plague, which marks the crifis. Thefe forms of malignant fever have never occurred in America, as epidem- ics ; but purple and livid fpots, vibices and all the variety of eruptions, which belong to that clafs of difeafes, occur occafion- ally during peftilence. It is a remarkable fea,' and one that feems to have efcaped ob- fervation, that a peftilential conftitution of air in all ages and countries, produces epidemic diforders of the eruptive kind. I queftion whether in a fingle inftance, fince the days of Mofes, the real plague, ever became epidemic, without one, two or all of that kind of difeafes for its precurfors. We cannot look into an author, who has defcribed the difeafes which prevail in fuch Vol, II. ' J7d 2lS a conftitution, from Hippocrates down to our time, but we fee ignes facri, variolas, morbilli or other eruptive diforders, confti- tutirig a part of the defcription. Thefe difeafes feem evidently to be claffed by the laws of nature, and always to appear, in clofe Conneaion. Hence the propriety of Sydenham's obfervation, p. 120 that " the eryfipelas, ignis facer, is a good deal like the plague, and fometimes accompanied with pains in the glands—that it begins much in the fame manner as the plague, but the plague is much more violent than an eryfipelas." Hence alfo we obferve that Hippocrates, in defcribing a pef- tilential conftitution, mentions that before fpring appeared " eru- fipelata polla," many cafes of the eryfipelas, of a bad type, and mortal. De morb. Vulgar. Sec. 2. This is a curious phenomenon and worthy of inveftigation, that a particular conftitution of the atmofphere, fhould, in its different ftages or in different feafons of the year, tend to generate all thofe difeafes, which throw out upon the furface of the body, petechias, vibices, a general efflorefcence and tumors, with various other appearances. It belongs to medical men to explain the general proximate caufe, which, while its effeas are varioos, ftill gives to difeafes fome common fimilkude. In America, a peftilential conftitution exhibits the fame phe- nomena, as meafles, and anginas, but without the purple or fpotted fever, as the precurfor of our peftilence. The immedi- ate precurfors of the bilious plague in America, are catarrhous affeaions, diforders of the throat, and efpecially bilious fevers of a bad type, ending often in black vomit. Detached cafes of this latter difeafe rarely or never fail to introduce or precede the in- feaious epidemic. But no difeafe whatever feems more clofely conneaed with peftilence than catarrh. An epidemic influenza, is almoft inva- riably the fignal of the approach of a peftilential conftitution ; and during the whole exiftence of the conftitution, catarrhous affeaions are frequent in particular feafons, and efpecially juft before or after the prevalence of a peftilential fever. This cir- cumftance affords no inconfiderable evidence, that what we cajl 219 an epidemic conftitution aas upon the human body as a violent ftimulus. The firft difeafes excited by it are ufually of the in* flammatory diathefis as catarrh and meafles. Hence perhaps we derive a clue to explain the myftery of the peftilential difeafes which fucceed. The continued effea of exceflive ftimulus, muft be debility. The epidemic conftitution, when it firft commences, is mild, and produces ftenic difeafes, not very mortal, as catarrh and meafles ; for a very obvious reafon, the force of the ftimulus is not at firft fufficient to haften on the indirea debility of the fyftem, or to produce the aftenic diathefis in a fatal degree. But as this ftate of air advances in ftrength, the ftimulus is greater ; and when aided by the heat of fummer, produces a degree of excitement, that fpeedily induces univerfal debility. Hence the peftilential fevers of fummer and autumn feem to be the effea of exceflive ftimulus, aaing upon the fyftem with fuch violence, as to produce foeedy debility, in confequence of which, all the funaionsof the fyftem are weakened and deranged—the ftomach does not digeft food—the periftaltic motion is imperfea and feeble—the liver and the gall-bladder do not perform their fecretions—the energy of the brain is diminifhed—the extreme veffels are relaxed. The con- fequence is, that part of aliment which ought to be feparated and carried off by the inteftines, as the hepatic fluid, is retained, and forced out of its proper duas, into other parts of the fyftem, where it excites external eruptions, efflorefcence, or yellow- nets ; in every part of the body, becoming rank poifon, and fpeedily inducing fever, morbid affeaions, and diffolution. This procefs is infinitely modified by fubordinate caufes ; as feafons, which are extremely various ; local exhalations and ftag- nant air, which are deleterious according to their force j the vari- ous modes of living, which ftrengthen or weaken the human body; and accidental circumftances, as fatigue, grief, fear, expofure to exceflive heat, or fudden cold ; and innumerable fimilar caufes. This idea of the proximate caufe of the bilious plague of our climate was imbibed from obfervation and converfation with phy- ficians, before I had read Brown's Elements of Medicin. I am happy enough to find, 'on reading that work, a confirmation of 22J the opinion. That author obferves, paragraph 137; ** Some- times the fecrctory veffels feemed crammed with a colluvies of fluids, capable of producing indirea debility, as in that over- flowing of bile, which diftinguifhes the yellow fever of the tor- rid zohe." This " colluvies of fluids," lodged in the fecretory veffels, feems to aa like poifon, in diforganizing the fyftem. And the reafon why the plague is fo often incurable, feems to be the ra- pidity and the imperceptibility of the aaion of that poifon, which appears totally to undermine the vital powers, before it exhibits much pain or fever. This is not its common mode of operation ; but it is not unfrequent. Cafes of this kind are foon charaaerized by a total proftration of ftrength, a cadaverous look, and a dull, glaffy, languid eye, fo often defcribed by med- ical writers. In fuch cafes, debilitating remedies precipitate death ; and ftimulants are ineffeaual to revive the languid func- tions. In moft cafes however the approaches of the difeafe are ac- companied with pains, uneafinefs, and febrile fymptoms, while the fyftem yet retains its ftenic diathefis ; in fome fuch cafes, de- bilitating remedies are ufeful ; but the rapidity of the progrefs of the poifon foon changes the diathefis to aftenic. Boyle remarks vol. 1. 672, " that a day or two before the plague has manifefted itfelf, in fome perfons, their vifion has been affeaed ; objeas appearing diverfified with beautiful colors. A vomit adminiftered to fuch, ufually gave relief." Every ob- fervation of fuch eminent men deferves confideration ; but I do not remember to have found the fame in any other author. If juft, 'is it not an evidence that the ftate of air, inducing the dif- eafe, operates firfl as afllmulus ? Procopius has recorded of the plague of 543, a phenomenon fomewhat fimilar to that noticed by Boyle. He fays, perfons imagined they faw phantoms or ghofts, which made them fuppofe they were fmitten by fome perfon. Such as had this imagina- tion, foon perifhed with the plague. In 746 alfo perfons were troubled with phantaftical images which filled them with terror. See alfo the plague in Carthage before Chrift 404. 22f General appearances favor the idea, that what is ufually called an epidemic ftate of air, produces, in the human fyftem, unufual excitement by exceflive ftimulus. But then how fhall we ac- count for the angina maligna, a difeafe of extreme aftenic di- athefis, which often forms one of the feries of epidemics, be- longing to the fame conftitution ? Is this alfo the effea of excef- five excitement, inducing great debility ? Is not its prevalence principally among children of found health, a proof that it is the confequence of indirea debility ? However thefe queftions may be decided, certain it is that under the fame conftitution, and during the fame peftilence, the fatal difeafes affume very different fymptoms, and exhibit, indif- ferent bodies, a different diathefis. In all epidemics of this fort, a principal objea of the phyfician is to afcertain the general di- athefis produced by the conftitution of air, and the various ef- feas of it in different bodies. " Hie labor, hoc opus eft."* The fecondary or auxiliary caufes of plague, coming under the denomination of Impure air, are fuppofed to aa upon the fyftem, by direaly debilitating powers. " It cannot be doubted, fays Brown, 145, that the application of air, to the whole fur- face of the body is a neceffary ftimulus. The air is feldom ap* plied in a pure ftate ; it is commonly blended with foreign mat* ters, that diminlfh Its flimulating power, and tho its falutary ftim- ulus depends upon its purity, it is uncertain whether ever its pu- rity goes fo far as to ftimulate in excefs and thereby produce ftenic diathefis." I know not what this author would call " purity of air," but I am very certain that an epidemic influ- enza proceeds from fome qualities in the atmofphere, and this author agrees the difeafe to be of ftenic diathefis. If the dif- eafe is the effea of " foriegn matter," infufed into the air, then this foreign matter is of a flimulating quality. * Is not the doArin of indirect and direA debility, as the fource of all difeafes fully implied in the firft paragraph of Ariftotle's firft pro- blem ? It may be thus rendered. " Why have great excefles a tenden- cy to produce difeafe, but becaufe they occafion too much or too little excitement, in which all difeafes confift." If this is not the precife idea of the author ; his doarin leads to the fame refults, as thofe which form the ingenious brunenian fyftem. Many things appear to us ne-w, which are *ooo years old ; and folely becaufe we neglect ancient au- thor*. 222 I fufpecr, however that the atmofphere fhould be confidered as eompofed of two principal fubftances, air and fire, or eleclricity. Morbid matter floats in the air, but the principal flimulating power probably confifts in the eleclricity of the atmofphere. The influence of morbid exhalations from putrefying fubftan- ces, is, probably to diminifh the ftimulant power of the atmof- phere, inducing direa debility. The lungs receive, at every breath, a certain quantity of air ; that is, about the fame cubic quantity. A certain portion of this, is vital air, oxygen, which ferves as food for the lungs and blood, and which is feparated from the reft and abforbed. Whenever therefore common air is impregnated with an undue proportion of hydrogene, or with any fpecies of acid, which is hoftile to the lungs, thefe vifcera waat their proportion of food, or ftiraulus ; the confequence is, their aaion is weakened, and the heart and arteries want their due force; the effea of which is a more feeble circulation of blood. Perhaps alfo the feptie acid, conveyed to the blood' with common air, at every infpiration, gradually deftroys its texture. Sorbait mentions that a lighted candle being placed near per- fons dying with the plague, a livid vapor has been feen, iffuing from their mouths. Extremely vitiated muft be the air from the lungs, before it can be rendered inflammable. But whatever may be the procefs, we know the effeas of refpiration in air vitiated by morbid exhalations, to be fevers of various kinds, as intermitting, remitting, dyfenteric, and putrid or peftilential. That ftate of the atmofphere which I call pefli- lential, has a lingular effea in increafing the irritability of the nervous fyftem, by which means flighter caufes than ufual occa- sion dangerous inflammation. Having then arrived at the probable caufes of the peftilential fevers which afflia the earth, we are prepared to confider the means of prevention. The firft article under this head, is, the removal of all local caufes of difeafe ; fuch as every fpecies of putrefcible fubftances, which, in the procets of putrefaaion, emit a fpecies of air highly unfriendly to health. It will be obferved that I fpeak of 223 putrefcible fubftances; for flefh or vegetables, which have under- gone the prpcefs of putrefaaion, or of digeftion in a healthy ftomach, difcharge little or none of the pernicious acid. Hence we obferve that people in cities rely too much on clean- fing ftreets to preferve public health. Experience proves that the utmoft care in cleanfing ftreets will not always prevent pefti- lence. The reafon is obvious ; moft of the filth of ftreets con- fifts of excrementitious matter from horfes or oxen, which has undergone the procefs mentioned, and contains no feptie acid, or very little. Hence the accumulation of dung in the farmer's yard, is not known to generate difeafes. Various other fubftances, thrown into the ftreets of cities, are more pernicious ; as green vegetables, the garbage of fifh, lees of fermenting liquors, and many others, which, in hot weather, foon putrefy and difcharge noxious air. Such fubftances how- ever never ought to be thrown into the ftreet in hot weather ; they fhould be thrown into the ocean, into rivers of running water, or what is better ftill, buried, and that before putrefaaion begins. If putrefaaion is begun, they fhould be removed in covered veffels. The vaults of cloacina, altho they contain moftly fubftances, which have paffed through digeftion, and in their unmixed ftate, are not very pernicious, yet they are always mixed with other fubftances, which, in hot weather, bring on fermentation. Thefe fhould be either cleanfed annually in fpring, or the matter in them neutralized by quick-lime. All filthy fubftances fhould be removed from ftreets, both for the fake of decency and of health. If the pavements of ftreets could be covered with pure earth, it would greatly leffen the heat ; but this is not praaicable. The only effeaual remedy, is frefh running water—the only article that unites cleanlinefe with coolnefs. Nothing, in a city, can be an adequate fubfti- tute ; for while it removes the caufes of noxious vapors, and by cooling the fultry air of a city, prevents debility, it extricates a confiderable quantity of new and wholefome air, from its own fobftance, and abforbs pernicious vapors. Streets thould alfo be fo conftruaed as to give the water a con- 224 fiderable velocity. The praaice of levelling the furface of a city, is moft pernicious. If poflible, every ftreet in a city fliould have a defcent of fifteen or twenty degrees. Inftead of levelling the earth, the police of a city fhould counteract even a natural level, by throwing the whole into artificial elevations j which give a brifker currency both to water and ak. Cellars fhould be fo conftruaed, as to retain no water ; and often cleanfed by fcraping. If the furface of the cellar can be conveniently changed, by removing a few inches of the old earth and introducing that which is frefh, it would be a very faj- utary labor. Nothing imbibes and neutralizes infeaious matter, more readily than frefh earth, The liberal ufe of water, in and about a houfe, cannot be too ferioufly recommended. Water abforbs all noxious matter that comes in contaa with it in fubftance. Applied to floors, wood- en, ftone or brick walls, to clothes, to furniture, to back-yards and ftreets; it is every where falutary in the fummer months, Dr. Prieftly obferves, that water purifies vitiated air, by abforb- ing the feptie part. Hence its great utility as a prefervative againft peftilential difeafes. All dead animals in a city or its vicinity, fhould be buried or burnt ; as cats, dogs and horfes. The indecency alone of fuf- fering their carcafes to putrefy before the eyes of mankind, ought to make it a ftria article of police, to remove .them. But they fhould be buried; not one fhould be permitted to offend the eyes or noftrils of a citizen.* They are offenfive to decency, to moral fentiments and to health. The ancient method of burning dead bodies was well calculated to deftroy the poifon ; but in Atlantic America, burial is cheaper and equally effeaual. Common fewers are often common nuifances. In cities, all filthy fubftances fliould be conveyed off, on the vifible furface of the earth, unlefs fewers can be fo conftruaed as to depofit, with certainty, all their contents in running water. Serious evils arife from putrid fubftances lodged in fewers, that are too level, and * From two years obfervations, made as I paffed dairy from New- York to my refidence in the country, I judge from twenty to thirty worn-out cart-horfes die and putrefy in the fuburbs of that city, every yej.% ' 225 which ferve as refervoirs inftead of canals, accumulating putref- cible matters, in places where their exhalations, by the influence of moifture, are doubled, inftead of being removed. In cities, where all filth is naturally eaft by rains into the docks, it would be well that all wharves fliould be fo conftruaed, as to prefent a fmooth uniform front to the ftream, and be exr tended into deep water. Mud, walked by the fait tides, and not mixed with putrefcible matters, produces no inconvenience to health ; but fuch matters, thrown into docks, bare at low water, and expofed to a hot fun, diffolve moft rapidly, and gen- erate morbid vapors. Many improvements are yet to be made in our fea-ports, which will leffen the accumulation of perni- cious air. A great and moft defirable article in a fyftem for the preferva- tion of health, is, the purifying of rooms from air which has been refpked for a length of time. By experiment it is found that the air of rooms that have been flept in, is very infalu- brious ; and probably more fo, than the air of privies, which is found to contain lefs noxious air than was formerly fuppofed. See Encyclopedia, art. Atmofphere. Indeed, it is queftionable whether there is any neceffary conneaion between offenfive fmells and infalubrity. Nature has kindly provided that dead feces fhould not be very pernicious to health ; but the effluvia of livr ing and fermenting bodies are to be avoided as rank poifon. In this refpea cleanlinefs is made effential to health. It is impoffible in a work of this kind to enter upon the details of cleanfing a great commercial city. The magiftrates, aided by medical men, in every city, will attend to the minute regu- lations for preferving a pure air. But there are other caufes of autumnal difeafes, which muft not be overlooked. It is remarked by writers that the difeafes from marines and ftagnant waters are moft violent near their fources ; and gradu- ally abate in their violence and become lefs common, as they re- cede from thofe fources. See Buel on the marfh fevers at Shef- field. Medical Repof. vol. 1.457. Hence, in a country gen- erally mountainous or hilly, dry and falubrious, but containing Vol. JL E e 226 here and there a pond of dead water or marfh, the bilious fevers generated by the effluvia, will be local, rarely extending beyond one mile and a half from tlieir fource. But there are fome extenfive marfhes, which may produce ef- feas to a much greater diftance. Such are the low grounds in Hungary, a fickly region ; the pontine marfhes near Naples, which rr.ay affea the health of people in Rome ; the flat lands and rice plantations in Bengal on the Ganges—the coaft of Ter- ra Firma in South-America, and the marfhes from E. Florida to the Delaware in North America. The fevers of Cambridge, Ely and Lincolnfhire in England, may be claffed with thofe above mentioned ; but are of fmaller extent. It is an opinion in Conftantinople that the frequency of the plague in that city, is to be attributed to the northerly winds, which come from the marfhes of Tartary and Ruffia, bordering on the Euxine, fweeping that fea, and conveying moifture and noxious exhalations. The pofition of that city is otherwife a very healthy one—the climate is temperate—the fite of the city, high, dry and riling into hills and mountains on the weft. No caufe of unufual dif- eafes can be found in the neighborhood. The caufes within the city, are powerful. Many of the ftreets are narrow, filthy, crou- ded, and almoft obftruaed by pent-houfes. But in this refpea, Conftantinople is not worfe than one half the cities of Europe, Shall we then admit that winds will convey morbid exhalations, feveral hundred miles, without dilfipating them, fo as to render them innoxious ? Let us attend to other feas. No city in Europe, except Conftantinople, has been more fre- quently defolated by plagues, than Rome, from the time of Rom- ulus to the clofe of the laft century. Shall we afcribe this, to the vaft marfhes which border the fhore from the mouths of the Tiber to Naples ? Certain it is, that Rome has ever been confid- ered, as a very unhealthy city ; and the terrible plagues which ravaged it, when in the utmoft profperity, as well as in modern times, juftify this opinion. So fenfible have the inhabitants been of the prevalence of this opinion abroad, and the ill-effeas of it in preventing ftrangers from reforting to the city, that Lancifius, 227 an eminent phyfician of the prefent century, wrote a confiderable treatife, evidently with a view to remove this opinion. This author obferves, that fouth winds at Rome, if violent, humid, with clouds and heat, produce inconvenience, and if they pafs over marfh, they may bring " particulas lethiferas," ve- ry pernicious vapors, which produce peftilential difeafes. The Romans very early took meafures to correa the evils to which the city was expofed. The enormous cloaca, or few- ers were raifed at a vaft expenfe, to carry off all ftagnant water, and dry the foil, and while kept clean, were very ufeful. Hence cloacina was deified as the goddefs of health. Thefe fewers Were under the care of certain officers, called " Curatores Cloa- carum Urbis." In one inftance, thefe drains had been a long time negleaed, and were cleanfed at the expenfe of a thoufand talents. Severe laws were enaaed, prohibiting individuals, un- der penalty of a fine, to fuffer water to ftagnate. Lancifius afcribes the fevere difeafes which affliaed Rome, in the decline of the Empire, to the deftruaion of the aqueduas and negfea of the fewers. In 1695, when the ditch of Adri. an's tower, and the great fewer of the city Leoninae, were filled with filth, immediately on the blowing of the fouth wind, began peftilential difeafes. By order of the Pope, at this author's fug- geftion, the ftreets, vaults, ditches and all fimilar places, were thoroughly cleanfed, and ten years after, no epidemic malignant difeafe had appeared. He however obferves that when a fouth wind blows for a long time, acute fevers, tertians, pains in the head, and vertigo become epidemic. This muft be occafioned by the debilitating effeas of that wind, or by miafmata convey- ed from a diftance, probably from the pontine marfhes. See Lancifius, paffim. Egypt is a flat country, containing not much marfh, but annual- ly overflowed, and fubjea to moft of the inconveniences of marfhy countries, from the drying of its moift furface, in very hot weather. Here again we have a nurfery of peftilence. The banks of the Euphrates and Tigris are nearly in the fame predicament, and Baffora, is in Perfia, what Cairo, is in Egypt. Moft of the coaft of South America, from Carthagena to the Oronoke, is bordered with marfh, and is every where fickly. 228 Bat what fhall we fay to the marfh on our own fhore : Th; low fwampy lands that border all the rivers, in the flat country of Maryland, Virginia and the Carolinas, and the iramenfe trad of bog in Virginia called the difmal ? The effeas of them on the neighboring inhabitants are well known—annual and almoft univerfal intermittents, and often, remittents. Is it not poflible and probable, that the noxious exhalations from thefe vaft hot-beds of putrefaaion, are borne on the fouth- wefterly winds, which prevail almoft conftantly in June, July and Auguft, and which run parallel with the general trending of the coaft, from Florida to New-York ? Do they not impregnate the whole atmofphere for a confiderable breadth, and fweep the country, from the eaftern fhore of the Chefapeek to Philadel- phia, New-Jerfey, and in a flighter degree, to New-York ? I do not give a pofitive opinion on this fubjea ; but the annual prevalence of flight intermittents on York-Ifland, and in the city, tho far removed from any marfh, and contkiually ventilated by fea breezes, as well as waflied by rapid tides, affords fome ground to believe this fuggeftion. It is confirmatory of this idea, that foon after leaving York- Ifland towards the eaft, all intermittents difappear ; unlefs in a very few places, where they proceed from obvious local caufes : Nowit muft be obferved, that the coaft of the United States, runs generally from fouth-weft to north-eaft ; but at New-York, it takes a different courfe, and runs about eaft by north, for two hundred miles. This courfe foon carries the people on the fhore, beyond the reach of the fuppofed ftream of morbid vapor, from the fouthern marfhes, whofe courfe is with the fouth wefterly winds. I am not attached to this idea ; but it is in conformity with the opinion of the infalubrity of the Euxine winds at Conftan- tinople ; and with the effeas of the foutherly Calabrian wind, blowing over the pontine marfhes, towards Rome. Lancifius relates a remarkable fea. Thirty gentlemen and ladies went on a party of pleafure, towards the mouth of the Tiber. The wind fhifted fuddenly, and. blew from the marfhes, " paludes pftienfes," and twenty-nine of them were immediately feized with a tertian. If fuch was the effea of the vapors from thofe 229 marines, we Inay fuppofe the vaft pontine marfh would poifon the air to a much greater diftance. That the extenfive moraffes, along our fouthern fhore, are pregnant with mifchief to that country is certain ; that the peo- ple of Philadelphia and New-York are affeaed by them, may be poflible. It would therefore deferve confideration, whether the evil will admit of a remedy. There are two modes of ren- dering marfhy lands and ftagnating water falubrious—one, by draining the lands and cultivating them ; the other, by turning into them ftreams of running water. It is probable that moft of the marfh at the fouthward, being within reach of tides, and below high water, is incapable of being drained. It is the pon- tine region of North-America. How far the fecond plan can be applied with fuccefs, I have not the local knowledge of the land and rivers to determin. The claflic reader will recolfea the inftance, related in hiftory of Empedocles, the Sicilian phi- lofopher and poet, who put an end to peftilential difeafes, a- mong the Saliuntii, by turning two ftreams of good water into the marfhes, from which they originated. If there is a poflibilky of drying any of the lands, now cov- ered with poifon, or of putting the dead water into motion, the United States have a vaft intereft in effeaing that objea; and expenfes are not to be put in competition with the health and lives of our citizens. The fame remark is applicable to all the marfhes in other parts of the country, as about fome of the lakes ; and to all fmaller fources of difeafe, fwamps and ponds. In every poflible fituation, where ftagnant water contains vegetable fubftances in abundance, difeafes muft prevail. Running water, on the other hand, is falubrious. It not only does not exhale morbid air, but it generates frefh and pure air ; at the fame time, it creates a gentle breeze by its current, which helps to diffipate any nox- ious particles in its neighborhood which may arife from other fources. People in the country cannot be too careful in fefeaing a fpot for their habitation. The queftion, of continued health or dif- eafe, of long life or premature death, hangs very often upon the choice of a falubrious fituation for a houfe. *3° A farmer fhould never plant his dwelling by the fide of a marfh. Whatever may be the fituation of his lands, he is inex- cufeable, if he builds his manfion within a mile of the fource* of difeafe and death. Better for him to go a mile and a half to his daily labor, enjoying robuft health, than to live within the circulation of poifonous vapors, affliaed by difeafes for three months in the year. And when a farmer has the misfortune to be obliged to labor occafionally in the vicinity of ftagnant water, he fhould be careful not to enter upon the ground early in the morning, before the noxious vapors have been raifed and attenu- ated by the heat of the fun, nor fhould he continue there, till late in the evening. People in the country fhould fefea hilly or elevated pofitions for their houfes ; where the furface of the earth is dry, and there is a free circulation of pure air. There is another reafon —the water on high grounds is always better than in low, fwampy places. Water in flat lands ftagnates beneath the furface, as well as above ; but on hills, it is in conftant motion. Hence if men expea good water they muft feek for it on mountains, hills and riling grounds. The Arabians advife that houfes fhould be fet on high, airy places, near frefh water. When a choice of difficulties occurs, and men are compelled to live near marfh, they fliould endeavor to place their dwelling on the windward fide of the marfh, which, in America, is the fouth and weft; the fummer winds being from thefe points. This will often make a prodigious difference in the ftate of health. The fables of antiquity are moftly obfeure and not well under- ftood by the moderns ; but fome of them are eafily explained,and contain moft excellent leffons. The ftory of Python, the huge ferpent, which alarmed and infefted the world, until he was flain by Apollo, is of this kind. Python was generated by the aaion of heat on the mud and flime, which covered the earth, after the recefs of the water of Ducalion's flood. That is, Python was difeafe, proceeding from noxious exhalations, in hot feafons, which was deftroyed by Apollo, the fun, which dried and puri- fied the earth. See Ovid, Metam. lib. i. This fable had it's origin in Egypt, where Python was killed by Ifis and Orus. 231 Of what confequence is it that we read books, if we neither uoderftand nor praaife the leffbns they contain ? But after attending to every circumftance that can aflift in guarding health from the annoyances that are local and vifible, we have a further talk to perform, to leffen the effeas of that ele- mental principle of difeafe, which has been proved to exift, in every clime, at certain unequal periods. If, it will be faid, fuch a caufe of epidemic difeafes, does in fea exift, and operate on every fpecies of life, vegetable and animal, this caufe is above hu- man control ; all our efforts to avoid its effeas, are ufelefs ; and we are doomed by the decrees of heaven, to be the viaims of peftilence, without hope or remedy. To this I anfwer j that if all hiftory is not a forgery, the ftate of the elements, has, in few inftances, been fo ill-adapted to fup- port health and life, or fo pofitively pernicious, that men have perifhed by millions, in the moft healthy regions, expofed to no local caufes of difeafe whatever, except fuch as exift in the moft healthy periods. This I muft believe ; but the fea affords no ground of complaint againft providence ; for the fame fate has attended all other fpecies of animals. The horfe, the ox, the ffieep, the dog, the cat, the fowls, and the fifh, are fubjea to the fame univerfal law of the phyfical world ; and on what prin- ciple will man arraign this difpofition of all created life, or claim an exemption from the laws, to which all other fpecies of animals are fubjeaed ? But we are not altogether without hope, even in the defperate circumftances mentioned. If we attend to the caufes of plagues, we fhall find they all tend to deftroy life by one generalef feci, which is, debility. Either direaly or indirealy, all the ex- citing caufes clofe their operation on the fyftem, by inducing de- bility, leaving the nerves, mufeles, and inteftines in a relaxed, languid ftate. If this principle is juft, and it is agreeable to the medical idea that debility is the caufe of all fevers, we have a clue that will lead us to the means of efcaping the evils of neftilence. In the morbid ftate of air, producing the uncontrollable pefti- lences, which have aflailed man in the healthieft fituations on the 232 globe, we obferve that the moft terrible effeas have been pro- duced, in feafons, when the air has been warm, humid, une- laftic, with light foutherly breezes ; as in the reign of M. Au- relius, of Gallienus, and of Edward III. This ftate of the air ferved very much to aid the peftilential principle, in debilitat- ing the human body. All local caufes probably tend to the fame effea. The great defideratum then is, how to counteraa the debili- itating operation of thefe caufes, and preferve the tone of the fyf- tem. I am perfuaded that all the means of prevention are com- prifed in that idea. No man is taken ill with this furious difeafe, until his nervous fyftem and his inteftines ceafe to perform their ufual funaions, and fecretions are fufpeuded or diminifhed. Hence perfons, as long as their evacuations are regular, may walk with fafety in the moft infeaed places, until their eyes and their color exhibit the poifon that is imbibed; yet they will not fuffer by the difeafe, while the veffels have ftrength to difcharge the morbid matter by regular fecretions and evacuations. This is a known and a common fea. Hence fome perfons and even phyficians have reforted, du- ring the plague, to fmall dofes of calomel, or other purgative, to keep open bowels. A moft pernicious praaice to thofe in health, fork induces the very evil meant to be avoided, debility; and ultimately, the inteftines becoming unable to perform their funaions, difeafe and death enfue. I am well informed of a number of cafes of this kind, in New-York, the laft fummer, which ended in death. The true means to preferve the natural tone of the body, are the mofl natural means. Firft. Food is the natural ftimulus of the fyftem. During peftilence therefore this article demands the firft notice. It is agreed by all writers, and obfervation juftifies the opinion, that temperance is effential to health, during a fickly feafon. Some perfons, miftaking temperance for abftinence, have run into an extreme of abftinence, which has been fatal to them. The true point to be obferved, is, to take as much food and drink, as will fuftain the body in its ufual degree of ftrength ; without *33 overcharging it with ftimulus. Too much food produces unufual exckement, which is followed by indirea- debility, a ftate of body which invites an attack of peftilence. Too little nourifh- ment, on the other hand, induces direa debility, a ftate equally favorable to difeafe. I have good grounds for believing fome very valuable citizens of New-York, of my acquaintance, fell facrifices to their excefs of caution in the ufe of food, during the laft epidemic. It is .not improbable that different conftitutions of air, as they produce various fymptoms in the fame difeafes, may require or admit of very different degrees of ftimulus, applied to the hu- man body. The epidemic in New-York in 1795, like that in Philadelphia in 1793, was charaaerized with inflammatory di- athefis, more frequently than in 1798. Hence venefeaion, which had acquired great celebrity in 1793, loft part of its credit, in. 1798, and was ufed with more difcrimination and caution. I fufpea the fame circumftance has changed or modified the opinion of the great utility of abftaining from generous diet and liquors. This opinion was general and well received in 1795 J nor have, any cafes come to my knowledge, in which the praaice was fuppofed to be injurious. But in 1798, many inftances oc- curred where perfons of the moft flender habits, of ftria abfti- nence from flimulating diet, and who weakened the fyftem by nurses, were feized with uncommon violence by the peftilence, and perifhed. On the contrary, I am acquainted with feveral phyficians, who took their ufual quantity of food, with fome wine and more than their cuftomary quantity of porter, who at- tended the fick, thro the feafon, vifiting the moft infeaed places, without fuffering the leaft inconvenience to their health. If the point is admitted that debility is the great proximate caufe of this difeafe, which I think cannot be contefted, the confequen.ee is plain, that whatever tends to reduce the vigor of the fyftem below its ufual ftandard, muft be prejudicial, during its prevalence. Hence the propriety of rather increafing than lef- feniog the ufual quantity of food, or natural ftimulus; carefully avoiding, at the fame time, all excefs in eating or drinking, which, is equally dangerous. ' Vol. II- F f 234 Another thing to be obferved, in fummer, and efpecially in time of peftilence, is, the guarding the body, but by all means, the head, from the direa rays of the fun. Nothing is more dange- rous than the burning heat of a clear fun, in fultry weather. It often produces fudden death, by means of an apoplexy, inftan- ces of which are related under the year 1752, to have happened at Charlefton ; and the fame is faid to have taken place there, the fummer paft. In other cafes, the effea is, what is called a ftroke of the fun, " coup du foleil," which is not always fatal, but- very dangerous. But the moft general ill-effea of expofure to a hot fun, is, great debility, in confequence of the violent and unnatuaral ex* citement ; and this effea is moft to be found in the nervous fyf- tem, when the heat has fallen direaly on the head. Convalet cents from bilious fevers have occafion to be particularly cautious, not to to expofe themfelves to a hot fun ; a relapfe is the moft certain confequence. The umbrella is an excellent invention ; it would be ftill more excellent, if it could be improved, fo as to render the fhade more general, and completely interrupt the rays of the fun, with- out being rendered too heavy. In walking the ftreets of a city, in a clear hot day, the paffen- ger will naturally feek the fhady fide. Of fo much importance is it thought, in fome hot countries, to fhield the body from the rays of the fun, that very difcerning men contend that narrow ftreets and high houfes, in cities, contribute to the health of the citizens, by mitigating the heat. They fuppofe the obftruaion of air a lefs evil, than a hot fun. Of this opinion was Lan- cifius. But this is to embrace one evil, in fhunning another. It is to be regretted that the beft mode of fhielding man from a hot fun, is not adopted in cities. Wide ftreets, bordered with rows of trees, would be infinitely preferable to all the artificial fhades that can be invented. Trees are the coolers given to us by nature. They make a pleafant fhade—they imbibe the feptie fluids, which"impregnate the atmofphere of cities, and poifon their in- habitants—they exhale pure air—they fan the earth, by creating 235 or augmenting currents of air, with the vibratory movement of their leaves—they invite the feathered tribe to light on their branch- es, and with the mufic of their notes, to relieve the ear from the grating of rough, unnatural founds, which ftun the citizen. It has been objeaed to trees, that they'increafe the danger of fire, by obftruaing the free ufe of engines. This objeaion is im- aginary. Few cafes would occur, where trees, properly placed, could interfere with the operations of extinguifhing fire ; and in fuch cafes, they might be levelled in a moment. It has alfo been objeaed, that trees obftrua the free circulation of air. This is not true. In calm fummer weather, they very much increafe a light breeze, by partly obftruaing the upper cur: rent with tlieir branches, and throwing more air below, thus augmenting the under current on the furface of the earth, where it is wanted. The leaves and branches alfo, by their gentle mo- tion, agitate the air, preventing the ill effeas of ftagnation ; and give velocity to the air that finds ks way through their interftices. " The ftreets and public fquares of a city, fays St. Pierre, fhould be planted with great trees of various forts. A city, built N of marble, would to me have a melancholy appearance, unlefs I could fee in it trees and verdure." Studies of Mature, 13. Trees and all green vegetables diminifti greatly the heat near the earth ; and little do men in general think, how prejudicial to health is the operation of the extreme heat of cities. It is not an uncommon thing in the country, where no miaf- mata exift, tor laboring men to over heat themfelves in the field, and die in fix days, with a bilious fever ; their bodies as yellow as faffron. This is yellow fever of a mild kind, generated in the fyftem, by the debility occafioned by exceflive heat and fa- tigue, without any external caufe. Thus the extreme heat of Auguft and September 1798 will alone account for the unufual violence and extent of the peftilential fever of that year. In the warm feafon, and efpecially in time of epidemic fevers, people fhould be doubly cautious not to expofe their health by ex- ceflive fatigue. Labor fhould not be violent, and walking, mod- erate. In extreme heat, the natural excitement of the fyftem, is ufually too great ; and a fmall addition to it throws the body 236 into a ftate of debility which invites difeafe. Not only health, but life, is often fofpehded on the point of half an hour's exer- eife. Temperance in labor, bodily or mental, is as effential to good health, as in eating or drinking. The mufcles and the nerves, thofe moving powers of the human body, if ftimulated beyond a certain point, lofe their excitability, beyond the pofli- bility of recovery. The danger incurred by fedentary and ftudious men, during peftilence, from the debilitating effeas of their occupations, is greatly increafed. Want of due exercife is direaly relaxing to the folids ; while application of the mind is apt to over-excite the nerves and induce indirea debility. The extreme irritabil- ity of the nervous fyftem, is obvious in a peftilential ftate of air. —I experienced it moft fenfibly in the fummer of 1795, during the fever in New-York ; and it is evidenced in the vertigo, fo •frequent at fuch times ; in the feizure of many perfons in the plague with apopfeaic fymptoms ; and in the palfies and apo- plexies which are greatly multiplied before or after the preva- lence of a peftilence, and which in fome places, have become almoft epidemic. During the rage of epidemic peftilence, alfo the animal ap- petite fliould be indulged with moderation—exceflive indulgence, which might have been fuftained at other times, has often hur- ried the young and fprightly, to a premature grave. Nothing can be more dangerous, according to all medical writers on this fubjea. Celfus dkeas that in peftilence, perfons fhould feek frefh air, travel, fail ; or if thefe are not convenient, they fliould avoid fatigue, indigeftion, cold, heat, exceflive indulgence of the an- imal defires ; efpecially fays the author, in a peftilence which is occafioned by foutherly winds. Vol. 1.40, 41. Thefe obfervations are not new ; they are common and well known to medical men, and to all others of difcemment. They are here inferted, becaufe they may be, in this work, more gen- erally read, than in medical books, which are opened only by profeffional men. *37 But all thefe rules, if ftrialy obferved, will not, in a mote violent plague, be fufficient to fecure the body from attack* Such are the extremely debilitating qualities of the air, in fome periods, that it will be neceffary to counteraa them by artificial powers pofitively tonic. The application for this purpofe, which is moft eafy and ef- feaual, is water ; an article which nature has furnifhed in the greateft abundance, becaufe it is far the moft ufeful. On this fubjea perhaps fome of the following ideas may not be very common. My attention to water, as a preventative of peftilence, was firft excited by a pafTage in Volney's Travels in Egypt and Syria, chap. 17. where he informs us in a note that " at Cairo, it is obferved, the water-carriers, continually wet with the frefh wa- ter they carry in flcins upon their backs, are never fubjea to the plague."—The author is there fpeakirtg of the pernicious effeas of humidity on health ; but the efeape of the water-carriers, he afcribes to lotion, whofe effeas are different from thofe of moif- ture by vapor. If this fea is accurately ftated, it is worth an empire. I am inclined to believe it and to afcribe the efeape of thofe men to the conftant application of water to their bodies, during the la- bors of the day. Yet if true, why have not authors propagated the knowlege of fo important a truth, to every part of the world ? Is this negfea alfo the fruit of the pernicious errors ref- peaing the eXclufive origin of the plague from infeaion ? The calamities fuftained by mankind, in confequence of thofe errors, exceed all calculation. How is it poflible, that, if a remedy for the calamity of pef- tilence, is fo obvious and fo near at hand, the Egyptians thould not have applied it univerfally ? Can this be afcribed to the doc- trin of predeftination, which makes them carelefs of the means of prevention ? It is very certain that the laws of Mofes, refpeaing the pro- hibition of blood, fat, fwine's flefh, and certain other animals ; as alfo the whole fyftem of ablutions, purifications, and ufe of perfumes, were intended to correa the evils of the climate ; and 238 many of his direaions became totally ufelefs, when the IfraeliteS left that country and its vicinity. Heaven never could intend fome of the provifions of the Mofaic code, for more temperate and healthy climates. The ancient Egyptians had fimilar praaices, and probably long before the days of Mofes. Their laws and cuftoms to en- fure cleanlinefs were very ftria, and they involved a moft liberal ufe of water. Herodotus exprefsly declares that " they fcour their cups, wafh their linen, and clrcumcife for the fake of clean- linefs. The priefts bathe twice by day and twice by night, and are obliged to wear linen." Swine's flefh was alfo confidered to be unclean and prohibited as an article of food. See Book 2. Euterpe. Thefe regulations doubtleis proceeded from the experience of their good effeas. It is not improbable that the introduaion of the Mahometan religion, may have been accompanied with the abolition or difufe of ancient praaices, which were friendly to health. Certain it is, that the oriental nations make great ufe of baths; the original defign of which was probably to guard a- gainft difeafes, but which have been abufed and converted to the purpofes of luxury. Let us then purfue the idea of applying water as a panoply againft the attacks of peftilence. By what means does water guard the body from that difeafe ? I have already quoted the obfervation of Dr. Prieftley, to prove that water abforbs the feptie acid. If this opinion is well founded, and I have no doubt of it, we have obtained a moft effential item of knowlege. Frefh water frequently applied to the body receives and carries off all the matter of infeaion, thus removing one copious fource of the difeafe. Savary remarks, that peftiferous matter, paffed through wa- ter, will not communicate the diftemper. This is a confirma- tion of Dr. Prieftley's principles. The ceffation of the plague in Egypt, on the inundation of the Nile, is no fmall evidence of the fame principle. The wa- ter changes the ftate of the air, both by abforption, that is, im- bibing and carrying off the peftiferous fources of vapor from the earth ; and by extricating a quantity of frefh air. And this 239 important faa direas to the mode by which all great cities are to prevent or leffen the force of this difeafe. What the Nile does once a year for Egypt, frefh ftreams of water thould do every day, in the hot feafon, for all large towns—they fhould inundate theflreets. Nature has given, in Egypt, the moft an- cient and the moft common nurfery of the plague, the model of the beft remedy for the fevereft calamity incident to man ; a model which few cities have been wife enough to copy. But it will, not be fufficient to truft wholly to the effea of a diffufion of water over a city. In the hot feafon, it fhould be applied to the body very frequently in the way of lotion or bath- ing. By this I do not mean to recommend the praaice of leap- ing into river or fea-water, and continuing in it for half an hour —a praaice which proves fatal to many lives every fommer. Cold water is the moft powerfully debilitating application, that can be made to the body. No perfons can bear it, even in fummer, but the healthy and robuft ; and to fave fuch from injury, it mull not be applied when the body is over-heated, or continued too long. Many-^-many inftances occur every year, in which a fa- tal yellow fever is fpeedily induced by injudicious plunging. An inftantaneous application of cool water to the body, by a fingle plunge, or by a fhower bath, fometimes aas as a ftimulant, by a fudden increafe of excitability in the fyftem ; but this fhould be ufed as a remedy, under the direaion of a phyfician. Few per- fons can fuftain the fhock, unlefs in good health ; and I am per- fuaded it would be as well for mankind, if the ufe of cold wa- ter by plunging, were wholly profcribed. Judicioufly applied, it is fometimes ufeful ; but my own obfervations lead me to be- lieve, the utility is more than overbalanced by its fatal or mif- chievous effeas. The moft fafe, eafy, pleafant and beneficial mode of ufing water, is, to bathe or wafh the body in a private apartment at home. This may be done in feveral ways—either in a large vef- fel immerfing the whole body at once ; or, what is lefs trouble- fome, with a fingle pail or bowl of water, in a bed chamber. The wafliing may be done with the hand, or a fponge, in a few minutes, as the perfon rifes in the morning or retires, at night. 24Q The temperature of the water fhould be near that of the, bipod ; a little cooler or a little warmer, and in fuch a temperature, it is a pleaiant application, occafioning no violence to the fyftem. It may not be obvious to every commor/reader, that the ap- plication of warm water to the furface of the body, in a hot day, fliould cool it. But fuch is the fea, and nature points out this mode of reducing the heat of the body, by the procefs of perf- piration. In this procefs, the infenfible vapor, which efcapes by the perfpiratory duas, takes with it a portion of heat—and the more freely a perfon perfpires, the more temperate, the heat of his body. Hence the human body is enabled to fuftain heat, feveral degrees above that of the blood—and hence the flefh of a child, in full health perfpiring freely, feels cooler than the air, in a fummer's day. This phenomenon may be illuftrated by a thermometer, with the utmoft eafe. Immerfe the bulb into warm water, in a hot day. Let the water be of 75 degrees of heat and the air, of 80 degrees. The thermometer, Handing at 75 deg. in the water, and taken out into a warmer medium, the air, ought to rife to 80 deg. but being wet, the evaporation will fink the mercury four or five degrees ; that is to about 70 deg. until the inftrument is dry, when it will^ rife to 80 deg. the temperature of the air. On this principle warm water, as well as cool, will leffen the heat of the fyftem ; for no fooner does a perfon ceafe to apply the water, than evaporation commences and cools the body by feveral degrees. This effea however is temporary, in confe- quence of the ftimulus of the heat. In very hot weather it is better, efpecially for perfons in th; vigor of health, to ufe water a little cooler, than the'blood ; for the effea of warm water, applied in the manner propofed, is to ftimulate'—and this is not what the body requires. On the con- trary, when highly excited by the heat of the air, the body re-^ quires a reduaion of heat, to prevent over-excitement, and its effea, indirea debility. In general then the body in fummer is to be cooled by the ufe of water, while in a healthy ftate ; but if debility or difeafe has invaded it, it, requkes heat and excite- ment. 241 1 Perfons of aflender habit, who require additional ftimulus, should ufe water a little warmer than the blood. The effea of cool water applied to perfons in full health, and of warm water, to feeble habits, is the fame ; to prevent debility ; indirecl in the former cafe, and direcl, in the latter. Bathing a long time in very warm water, to produce profufe perfpiration, is a powerful laxative ; and perhaps it would be bet- ter, if it was never ufed, except as a remedy for difeafe, under the direaion of phyficians. The beneficial effeas of the ufe of water, in peftilence, there- fore, are thefe.—The poifonous particles compofing infeaion, and exhalations of all kinds, are waflied from the body, and their ill effeas prevented—the morbid matter exhaled from the body by- the perforatory veffels, is alfo removed—an effea that may be aided by frequent changes of clean linen.—The extreme veffels are ftimulated and cleanfed, by which means they are enabled to carry on more perfealy the excretions ; perfpiration being one of the principal refources of nature to expel the poifon which enkindles the flame of peftilence.—The whole fyftem is kept in equilibrio, by a diminution of excitement, in the robuft, and an increafe of it, in the debilitated ; the confequence is, the fyf- tem is daily renewing its tone and vigor, the energy of the brain is preferved, the mufeular fibres retain their powers, and all the funaions of the body, the digeftion, circulation, fecietions, and evacuations, are regularly performed. Medical gentlemen will excufe me for thefe ideas, which be- long more properly to their province. They are not new to that defcription of citizens ; but, if juft, they ought to be univerfal- ly known ; for they lay the beft foundation for a regular plan of economy, in domeftic life, which will greatly alleviate the dif- treffes of autumnal epidemics. I cannot help thinking that man- kind are yet in their infancy, in this refpea ; and that in general they underftand the true art of living, which fhall fecure health and happinefs, as little as they underftood agriculture or naval architeaure, in the days of Henry the firft. I am perfuaded that the whole art of fecuring ourfelves from Vol. II. G g _242 peftilence, as I have before remarked, confifts in this fimple maxim—" preferve the natural energy of the fyftem." That water, frefh and pure, is the inftrument moft efficacious for this purpofe, I muft believe, from reafon and experiment. The faft related by Volney of the efeape of the water-carriers, is of infi- nite weight, if fairly ftated ; and demands immediate applica- tion to our own cafe. At any rate, it demands inveftigation. I have other proof of the fuccefs of water, ufed as I have prefcribed. A friend of mine, who has lived many years in the Weft-Indies, who has feen the yellow fever in all its forms, who has tended the fick in that climate and in New-York, expofed himfelf to their breath and effluvia for days and nights fuccsflive. ly and flept with his own fon, when on his death bed, with that difeafe, has hitherto efcaped the infeaion. He afcribes this im« punity to a daily ufe of water in the manner abovementioned. We are not to calculate on the univerfal and invariable fuccefi of any remedy for .this terrible calamity. Multitudes of men will not take the pains to ufe the means neceffary to refift the ef- feas of the numerous caufes of difeafe which furround them. They will neither regulate their diet, nor cleanfe their perfoni and habitations ; and when to the influence of their own intem- perance, and the poifon generated in their houfes and on their bodies, is added the debilitating operation of peculiar feafons and other caufes which are above human control, great numbers of them muft fink and perifh. Nor is it to be fuppofed that any human means can, in every cafe, guard life, in a peftilential ftate of air. If we admit de- bility to be the univerfal proximate caufe of the plague, we are not fere that our beft efforts to obviate its effeas will always fuc- ceed. We may not be able to find or to apply, in all cafes and under all circumftances, the precife degree of ftimulus, neceffary to preferve the corporeal funaions ; and the variety of conftitu- tions, and diverfe operations of the fame remedies on different bodies, will defeat, in fome cafe3, the moft exaa application ojf. the beft poflible fyftem. Of one thing I am confident, that, in our cities as now con- ftruaed, no rigors of police can fo. etfeaually cleanfe av, ay thr 543 fources of poifon, as to prevent a return of peftilence, without the univerfal introduaion of a new domeftic economy, and new modes of living. I am firmly perfuaded that fruitful fources of the evil lie in thefe two articles—the exceflive ufe of ftimulant food and liquors, and the negfea of perfonal wafting. The diet of the Americans, like that of the Englifh, is of the moft nourifhing kind—a large portion of the beft flefh meats, and high-feafoned fifh and vegetables. Our drink is of the fame charaaer—the beft high wines, fpirits and brandy. In winter, our bodies fuftain this ftimulant mode of living ; the extreme cold continually refilling its effeas by its debilitating powers. But when fummer arrives, and the violent ftimulus of heat, is added to the high ftimulus of the beft diet, two clafles of men fall a facrifice to violent fevers. Firft, men who pufh their ftimulus beyond the powers of nature, by exceflive exer- tion, and imtemperance in eating and drinking—hence a robuft man riots in debauch to day, and four days after is in his grave. Secondly, men who live freely in winter, and reduce their diet too low in fummer, to avoid difeafes, inducing a weak, languid ftate of the fyftem. It muft be obvious to any perfon in America, that the French mode of living, in regard to diet, drink, and the liberal ufe of water, proteas them from the epidemic difeafes which prey up on the Americans, and Britifh natives. Nor have I the leaft doubt, that a fuitable regimen, purfued rigoroufly by the Euro- peans, would have faved one half the people, who perifhed in the black peftilence in 1348. Unfortunate fouls ! They believed the plague to be communi- cated by infeaion only ; they fought fafety by flight; they em- barked on board of veffels, and launched out upon the ocean, to efeape infeclion ; but all in vain ; the difeafe attacked them in ev- ery fituation, and the world was almoft difpeopled. Had they known that the diftemper was induced folely by the debilitating qualities of the elements and the feafon, what multitudes would have applied the true remedy, and furvived ! Thanks to a kind providence, fuch a Angularly depreffing ftate of the air, rarely occurs, but when it does, there is no flight from the fources of dif- 244 fife, as in ordinary plagues, which arife in the impure atmofpher^ of cities only ; but men muft have recourfe to the applications which refift the effeas of debility, and maintain the energy of the fyftem by fupplying the defeaive powers of the elements, with artificial ftimuli. I cannot clofe thisfeaion, without a few remarks on the gen- eral plan of building large towns. The ancient mode of conftruaing cities bears fome cliarafter- iftics of the age and tafte of the nations, in which they were re- fpeaively founded. Moft of the old cities were evidently built with reference to a ftate of war and robbery ; being intended for fafety, rather than for convenience ; as appears by their narrow ftreets and the-projeaions of the upper ftories of the houfes. The more people could be crouded into a fmall fpace, the lefs military force was neceffary to defend the town. However this may be, thofe cities were very ill-conftruaed for the purpofes of health. Savary afferts that 200 perfons in Grand Cairo occupy lefs fpace than 30 in Paris. The ftreets are fo barrow and full of people, that they joftle againft each other, and fometimes a man is obliged to wait fome minutes, before he can make his way. Letter 3. Yet thisdame author alleges the plague to be not native in Egypt ! Surely a man of fcience need not go out of Cairo to look for caufes of peftilence. Many ftreets in Conftantinople are narrow and crouded like thofe in Cairo. Tne old city of London, before the fortunate conflagration of 1666, was in a like predicament ; its ftreets narrow and almoft clofed above by the jutting of the upper ftories of the houfes. In the old ftreets, which efcaped the fire, notwithftahding all the improvements of modern days, which have mitigated the violence of peftilential difeafes, I am informed people are ftill infefted with nervous and typhus fevers. London is however greatly in. debted to the conflagration. In the prefent conflruaion of the buildings, one perfon, it is faid, occupies as much ground as two did before the fire. The fize and arrangement of houfes and apartments are alfo improved ; and better adapted to a free ciicu- latjon of air. The introduaipn of frefh water may alfo benum- bered among the beft prefervatives from difeafe. Thefe arfea- mong the caufes of the non-appearance of the plague in modern London, and the diminution of the annual bills of mortality, within the laft half century. The plague however'has difappeared in other cities of Europe, where no fuch improvements have been made—a curious fea, that will be hereafter confidered. But the difeafe continues to prevail occafionally in the eaftern parts of Europe, in Hungary, Poland and Ruffia, which were feverely ravaged in 1770, and 1771. The difeafe alfo raged at Oczakow, on the north border of the Euxine as late as the year 1739. That part of Europe abounds with marfhes and ftagnant wa- ter, and confifts moftly of level land. This may account for the continuance of the plague, in that quarter. The United States unfortunately contain fimilar fources of difeafe, in number and extent fcarcely equalled. Yet inftead of profiting by the fevere diftreffes which all great cities have fuffer- ed once in fifteen or twenty years, from peftilence, and guarding againft the artificial caufes of it, our anceftors began and we are continuing to build cities, on the Gothic plan, without more re- gard to the lives and happinefs of our citizens, than that which was manifefted by the barbarians of antiquity. The moderns how- ever proceed on the fame plan from a different motive, which is, avarice. It is now the intereft of the proprietors of lots in a city, to which all the pleafure of living, and the health of citi- zens, are facrificed. We are precifely in the latitudes moft favorable to the produc- tion of peftilence. In the tropical climates, conftant heat foon fits the human body to fuftain it, and the natives of thofe climates are feldom affeaed by the furious rage of epidemic peftilential dif- eafes. Within the tropics flrangers alone are fufferers by the climate.* * Savary remarks" that the plague feldom reaches the polar circle and never panes the tropics. The caravans of Cairo, Damafcus and Ifpahan, which are fometimes infefted, never propagate it at Mecca, and Yemen is fafe from the plague." With few exceptions thefe obfervations are juft. If the natives of cool regions pafs fuddenly into tropical cli- mates, they are fuhject to violent fevers ; but the reafon afligned in th« 246 But in the temperate latitudes, men are continually fubjea fed the alternations of extreme heat and cold—changes hoftile to the fyftem. In winter, we may be faid to be inhabitants of Lap- land ; in fummer, of Mexico or the Weft-Indies. If we do not remove to the polar circles or to the tropics, yet the revolu- tions of the feafons bring their climates to us ; and we annually run a fimilar rifle with the Europeans, who pafg from the northern to the fouthern latitudes of peri/hing in multitudes. It is a moft unqueftionable fea that the northern ftates of A- roerica from New-York to M.aine, are in a pofition on the globe, as expofed to the plague as the cities of Marfeilles, Naples, Rome and Conftantinople ; and the fouthern ftates have a pofition cor- responding with the latitude of Syria, the Barbary coaft apdE- gypt; that portion of the earth which is moft frequently ravaged with peftilential difeafes. If then we live in a climate in which the human body, from alternate heat and cold, is moft irritable, and moft fubjea to ma- lignant autumnal diftempers ; and if a part of our country is pe- culiarly adapted to the produaion of fuch difeafes ; the moft fe- rious of all queftions arife3 ; what fhall we do to prevent a fre- quent return of fuch calamities ? To me, the path is extremely plain. Our climate we cannot change—much of our country cannot be raifed into hills, nor drained of its ftagnant waters—the laws of nature we are unable to control in the operation.—But our duty is plain. Men muft not plant their habitations near marfliy grounds—the mode of building cities mufl be totally changed—andfo muft the ufual hab- its of our citizens. Throughout the whole Atlantic territory, on the low lands, it is more effential that large towns fhould be purpofely conftruc- jed for health.—Great cities are ufually founded on commerce, and commerce requires the accefs of navigable water. Hence fuch towns are commonly near the fea fhore or on the borders of rivers.—But if they are near low marfliy grounds they cannot be tert is fufficietit to account for the perpetual exemption of natives of hot climates from the worft form of peftilence. Their bodies mould them- felves to the climate—their excitement or debility is always uniform. It is the great changes, in thefe refpe<3», which expofe people ir. the middle latitudee to the attacks of peftilential difeafes. 247 healthful. High and dry pofitions, with rocky or gravelly earth, are the proper places for populous cities, on account of frefh ai* and good water. But in any fitation, our cities are too crouded for health of comfort. Lots are too fmall—too many people are crouded on to a little fpace of ground. A family to every lot of 35 or 30 feet by 80 or 100, connot fail to generate too much filth, and to vitiate the air in too great a degree, for the health of the citi- zens. In every large town in the United States, however re- mote from marfh, and however healthy its pofition, the effeas of crouded population are obvious, every autumn, in the ficknefs and death of children. Multitudes and multitudes of lives are anually facrificed, in all cities, to the avarice of the original proprietors of lots. The little narrow dirty houfes, kitchen* and yards furrounded with high fences, excluding air and veget- ation ; all that can diflipate or abforb the noxious exhalations ; all that can purify the atmofphere and refrefh the exhaufted frame of a human being, panting beneath a fultry fun—-every thing in our cities is contrived to wafle the powers of Ufe, and fhorten its- duration. Men, in this refpea, are infinitely lefs fagacious than irrational animals. Inftina guides the beafts of the field to the moft prop- er habitations—and they never refide where they are annoyed. But man, with all his boafted reafon, fees the effeas of his fol- ly, and hundreds and thoufands of his fellow-citizens falling vic- tims to his own negfea, his miftakes or his fordid principles; he heaves afigh in Auguft and September, as he views the fable hearfe, conveying his friends in fcores to their graves ; in No- vember he fhrugs his fhoulders and fays, it is all over ; run8 to the circus, the theatre and the card room ; laughs away the win- ter's evening with his jovial companions, fome of whom are deftined, the next feafon, to fall a facrifice to the fame folly^tad negfea, and to fill new ranges of graves by the fide of the vic- tims of the preceding year. In the United States, every thing that has been done hitherto in the conftruaion of cities, is in imitation of the old European and African mode, and of courfe is wrong. 248 -The ancient conftrhaion of London coft that city nearly twa hundred thoufand lives in one century ; and Cairo and Conftanti- nople probably lofe more than that number, every half century, I firmly believe, and my belief is founded on the uniform ope- ration of eftablifhed laws of nature, that a perfeverence in ourpref- ' eiit mode of building cities, will doom them all to the fame fate. - I believe it, becaufe I fee no poflible reafon why peftilential difeafes fhould not be as frequent and as fatal in America as in the old world, under the operation of fimilar local caufes. * If a rigid police can be uniformly obferved ; and every potfi- bfe nuifance be removed by fhovels, brooms and water, cities in healthy pofitions, will efeape the regular and conftant return of malignant epidemics.—Multitudes of lives may be faved, and the lofs of bufinefs prevented, by thefe means ; and in cities al- ready built, cleanfing, wafliing and purifying, are the guardian angels of public health. ' But I maintain that this is not exterminating the root of the evil. Cities may be built fo as to unite all the utility of a town, wkh the falubrity and pleafures of the country, and in this new world, where men are as free to aa as to think, it will be dis- honorable not to invent and execute a plan for thefe purpofes. Were I called upon for a plan of a city, which fliould com- bine in it the advantages of town and country, I fhould fuggeft the following as the outline : 1. The pofition to be on the fhore of the fea or the bank of a river, gently afcending with an angle of at leaft fifteen or twenty degrees ; which would form a declivity for a rapid defcent of wa- ter to wafli the city ; at the fame time, would not prevent the, draft of heavy loads from the river or ocean. z. The wharves on the water fhould be extended beyond low water mark, that no part of the docks fhould be left bare by the redjtfs of the tide. All the folid front of the wharves fliould be : on a line ; that no eddies might be formed ; and the water might flow in a parting current. This would carry off fubftances thrown into the water, and contribute to keep the air pure by motion and change. Should it be neceffary to extend wharfing in one place further than in another,' it fliould be in the form of a bridge on piers. 249 , 3* The warehoufes on the wharves fliould not be jumbled to« gcther in a chaos ; one projeaing in front of another : but built in a ftrait range, at a fuitable diftance from the water ; and an alley fhould pafs between them for the admiffion of frefh air on every fide. No wet cellars fhould be permitted. 4. The ftreets fhould be ftrait, interfeaing each other at right angles, and forming the city into fquares of at leaft 500 feet on a fide. 5. The lots fhould be at leaft 60 feet wide, and 250 feet long. No more than 35 or at moft 40 feet of the breadth of the lotto be ev- er covered with buildings, fo that a fpace of 20 or 25 feet fhould intervene between the houfes. This fpace would leave a cartway, give free admiffion to air, and reduce the rifle of fire 75 per cent. 6. In the rear of the front building, out-houfes might cover 100 feet of the length of the lot. The remaining 150 feet fliould be laid out to the fancy of the owner in a garden—the po- lice interfering no farther than to require by law that fome kind of trees or vegetables fhould occupy the fpace—vegetation being the natural purifier of the air. 7. Direaly thro the center of each fquare, thould run a nar- row ftreet of about 25 feet taken out of the rear of the lots, which ftreet or alley fhould never be built on, but would admit a pafTage for citizens thro the fquares j and what would be ftill more neceffary and ufeful, would admit daft-carts to take up all the filth of the houfes, from the rear, and prevent that intole- rable nuifance, the depofiting of offenfive materials in the ftreets. The little flower gardens and fliady lawns in thefe fquares, would preferve the air pure, frefh and cool in fummer—they would oc- cupy many perfons of delicate health, thus contributing to their comfort, diveiting their minds, and in many cafes, reftoring them to health. Here alfo children would find room to gambol, without endangering their lives or annoying paffengers in the ftreets,; and here the young of both fexes would acquire a tafte for gardening, for botany, and the delightful amufement of ftudy- jng the works of nature. 8.. The ftreets fhould be one hundred feet in breadth, ann Vol. II. H h 25° planted with three rows of trees. One row on each fide next the foot walks, and a row in the center. The foot walks to be 15 feet wide. The trees next the walks would then be 15 feet from the houfes ; and a fpace between the center row and each fide row, of 35 feet. The trees might be fo pruned, as to prevent their injuring the buildings, and their diftance would prevent their interfering with fire engines. Thefe trees would be leaflefs in winter, when the fun is acceptable ; and in fummer would fweeten, purify and cool the air. The citizens at all times in the day, would walk in a refrefhing fhade—the center row of trees would furnifh fhade for horfes. 9. No city fhould be raifed on level earth. If a natural po- fition cannot be found, with a general declivity to the water, the ftreets fhould be thrown into artificial elevations of at leaft 3 feet in every hundred—five feet in the hundred would be better. ' This would give celerity to the water falling in fliowers, and wonderfully affift in removing filthy fubftarices from the ftreets; for after all human efforts in fweeping, much offenfive matter will remain, which water alone will reach and carry off. 1 o. No pains fliould be fpared to fupply a city with frefh run- ning water. It is a point of infinite importance that citizens fliould not depend on water from pumps in the city. In a few years, the fubterranean water becomes impregnated with the noxious parti- cles from vaults—and this evil continues to increafe with the age of the city. One of two remedies are to be provided—either the city muft be fupplied with frefli water by pipes from a diftant fource ; or the vaults muft be fo formed as to be capable of being opened in winter and cleanfed. But the laft method, tho ufe- ful and praaifed in fome European cities, would be ineffeaual. The back houfes in a city are, in many refpeas, a terrible nuifance. If a fewer could be carried four or five feet under ground, and every fuch houfe be fet over it, a flreani of water paffing thro it from a diftant fource, would be an excellent means of cleanfing a city from this fource of difeafe. But fuch ftreams of water are rarely to be obtained. Another expedient fuggefts itfelf for the fame purpofe. Let 3. fewer of three feet wide and well paved, be run in a fttait 251 fine under the rear of the lots, and all back houfes fet over il» In fuitable places, let channels be made to turn the water from the ftreets into the fewers, in long or violent fhowers, when the water is not wanted to wafh the ftreets. In this manner, the fewers might be waflied perfealy clean, a number of times every fummer, and the citizens preferved from their poifonous exha- lations. On a model of this kind, I conceive cities fhould be con- ftruaed in the mofl healthy fituations ; for a crouded population, in any place on earth, will leffen the falubrity of the air. Clofe compaa cities, in any quarter of the globe, are the graves of men. All the great cities of Europe require annually fome thou- fands of ftrangers to fupply their wafte of population. Yet there is no neceflity for men to croud together in fuch,.a compaa form. There is land enough on earth to fuffer any extenfion of cities, and it makes little difference, in the firft inftance, whether a lot contains one hundred feet of land or half an acre. Nor would a lefs denfe population be any inconvenience to men^ in bu- finefs. They might be obliged to walk further on fome occa- fions ; but in the cool fhade of my propofed city, this would be a pleafure rather than a toil. It is wrong, it is criminal, for legiflatures to permit fuch crouded population. It is a nuifance, not only to cities, but to the public. It is a truth, that numbers of lives are facrificed almoft every year, among worthy country gentlemen, who have bufinefs in our large cities. They come to town in the hot feafon, when no uncommon difeafe prevails among the citizens who are innured to the ak— they come without fufpicion—they are feized with fever and die. The ak of the low grounds in our cities, even in healthy fea- fons, is often poifon to people from the country, and gives them a fever, when no epidemic is vifible among citizens. I know the faa, and it is a ferious calamity, efpecially to feamen. The low grounds in Providence, New-York, Baltimore, &c. are great nuifances. The building of Water-ftreet and Front-ftreet in New-York, it is believed by good judges, has coft this city a thoufand lives in five or fix years. I fay nothing of Philadel- phia j for its pofition and the alterations in the original plan of 252 the city have doomed it to calamity. The citizens will not be-> ILeve the evilto arife among themfelves and therefore muft be left to thek fate.- If remitting fevers every year, and yellow fevejt often, will not convince men that fomething is wrong in their city, it is in vain to reafon with them. Of one thing I am con- fident, that if all the earth in New-York on which Water and Front-ftreets are built, could be funk 30 feet under water with- out lofs of lives, and the proprietors indemnified by the citizens, it would be the greateft blefling which heaven could in mercy beftow on the city and the ftate. I believe alfo, that if all the crofs ftreets and the back houfes in Philadelphia could be levelled with the earth, and the ground converted into flower gardens and grafs plats, the citizens would, in twenty years, cel- ebrate the anniverfary of their deftruaion, with as much ferror as the republicans in France celebrate the demolition of the Baftile. It is not poflible, I fpeak it with zeal and confidence ; it is riot poflible, under the operation of the prefent laws of nature, for men to be healthy in many of our cities, during the heat of fummer. That open champaign country, which regularly pro- duces intermitting and remitting fevers, will, when planted with populous cities, often produce the plague. Of that country, there is an extent in the United States, of more than one thou- fand miles in length, and from 40 to 60 in breadth. All the fhore of the Atlantic from the Hudfon north-eaftward will admit of healthy cities. If the commercial towns on that portion of America were conftruaed on the foregoing plan, I would anfwer for it, that they would never be ravaged with yellow fever. Individual cafes might occur ; but the difeafe could not, without a miracle, become epidemic. But as cur towns are now built they will at times be partially affeaed. In ordinary feafons and with a vigilant police they will efcspe, with... the yearly lofs of only ten, fifteen or perhaps fifty citizers, the unfortunate viaims of the negligence, the folly, and the crouded population of cities. In very unfavorable feafons, the number of viaims will be increafed. Such is the fate of our northern cities. But the deftiny of cities on the fouthern Atlantic fhorey is to be more fevere, =53 The period of general contagion may fubfide, and intervals of more general public health, may be expeaed. The moft un- healthy parts of the earth enjoy fuch intervals, when the rage of malignant complaints is fufpended. But the melancholy periods of epidemics will often recur—and as the plague, in all its fhapes, is the offspring of caufes, mankind, wherever thofe caufes exift, are deftined to be afffiaed. Away then with crouded cities—the 30 feet lots and alleys— the artificial refervoirs of filth—the hot beds of atmofpheric poifon. Such are our cities—they are great prifons, built with immenfe labor to breed infeaion and hurry mankind prematurely to the grave. There is no necefiky for this deftruaion of human life. Cit- ies laid out on my plan would unite all the pleafures of country villages, rural feats, and commercial towns. The merchant, in his ordinary bufinefs, would enjoy the grateful fhade of oaks and elms, with the luxuriant perfumes of odoriferous flowers. At the fame time, this verdant city would fuperfede the ufe of fol* itary country-feats in fummer ; and thus fave the expenfe now in- curred of poffeffing a town and country houfe. The country feat of a merchant, is a tax of ten, fifteen or twenty thoufand dollars, paid to maintain the poifon and peftilence of our prefent cities. It is remarked by Boyle and other authors that China is rarely affeaed with the plague. The peftilence of 1347 is faid to have commenced in that country ; but it feems to be agreed that China and fome other Afiatic countries are not often affeaed. This fea, if juft, deferves inveftigation ; in particular ought philofo- phers to examin the nature and properties of the foil and the min- eral produaions. China is a very populous country, filled with canals, and well cultivated. It is probable that the water in the canals is never ftagnant, nor filled with vegetables—it is probable that the face of the country has been completely dried by cultivation, all fwamps and moift grounds drained and covered with corn, rice and grafs. How much thefe improvements have contributed to preferve its inhabitants from peftilence, I need not inform my readers. ' *54 The cities alfo in China are vaftly large and populous ; and art enquiry will arife, how thofe cities efeape the plague, if great population contributes fo much to the calamity. I anfwer, they do not efeape all plagues—fome of the moft vi- olent have ravaged China ; but they probably efeape the flighter plagues, which are the moft frequent; and this is all that man- kind can expea. We are not fufficiently acquainted with the foil, climate, police and manners of China, to fpeak with certainty on this fubjea ; but one fea ought to be mentioned. The Chinefe houfes have no Windows in front, on the ftreet, but in the rear, are fpacious gardens filled with trees, vegetables, flowers, and frefh Areams of water. Here the family is regaled and amufed ; the air is ren- dered pure by cultivation, cleanlinefs, and the particles exhaled from growing plants, and water-falls. This arrangement alone will account for their exemption from the ufual difeafes of hot climates.—When the Americans, with their boafted light and fcience, fhall become as wife as the Chinefe, they may expea to fhare in the exemption. It is a fea related by Ruffel and others, that in the midft of the Turkifh cities, during a defolating plague, the fpacious man- fions of the wealthy Turks, which are kept clean, and well aired, often efeape the difeafe. I cannot leave this deeply interefting fobjea, without relating an anecdote from antiquity, which fhows in what light wife men formerly viewed it. In Greece, the countries of Attica and Lacedemon, confift of dry, gravelly or rocky land ; and I can find but one inftance, in which thofe countries were affeaed by peftilence, in the early ages. It is evident from Thucydides, that the plague had never been known in Athens before his time, fince the date of the earlieft traditions ; and then it was probably induced principally by the croud of people colfeaed in the fiege, to efeape the rava- ges of the Lacedemonians. Bceotia, on the contrary, was more frequently vifited by pefti- lence. To account for this, let us know what was the fituation of this country. It is thus defcribed* 25£ Bceotia may be confidered as a large bafon, furrounded by mountains, the different chains of which are conneaed by high grounds. Moft of the rivers from thefe hills unite in Lake Co- pais, of fourteen leagues circumference, which has no apparent outlet ; but, it was alleged by the ancients, to have fubterrane- an paffages into the fea. The country is not without hills, but is raoftly level, and very fruitful. The air in Attica is remarka- bly pure ; but in Bceotia, very denfe ; hence the ancients derived the heavy, phlegmatic charaaer of its inhabitants from the air. This country feems to have been to Attica, what Holland now is to France. See Travels of Anacharfis, Ch. 34 and the authorities there cited. From feveral paffages of hiftory, it appears that Bceotia was morefrequently vifited by peftilence than Attica. This we thould expea from the difference of thek fituations. Juftin, lib. 16. ca. 3. informs us, that the Boeotians once confulted the Delphic Oracle, how to remedy the plague that troubled them. The Oracle replied, " That they muft plant a colony in- the country of Pontus, facred to Hercules." But they were fo much attached to their own country, that they dif- obeyed the injunaion ; until another calamity, war, drove them to confult the Oracle a fecond time, when, receiving a fimilar anfwer, a part of the people removed to the borders of the Eux- ine, and founded the famous city of Heraclea. This Oracle certainly underftood the caufe of the evil, and direaed to a fuitable remedy. The anfwer implies, " you muft thin your population," or " you muft feek a more falubrious cli- mate," or it might comprehend both thefe ideas. The direaion is full of wifdom, and is ftrialy applicable to many of our Amer- ican cities. Tranflated into the language of our circumftances, it runs thus " thin your population, by fpreading your citizens over a larger extent of ground, or you will often .be driven from your cities, into the country." We have Mofes and the prophets, in books and experience, and if we will not liften to them, neither the Delphic Oracle, nor a meffenger from the thoufands of dead who have perifhed by the plagues of our cities, would induce belief or effea a reformation* 2^6 SECTION XVIII. Qf the difappearance of the plague In fome parts of Europe, and of new difeafes. J. T is a common remark that no plague has appeared in Eng- land, fince the year 1665, and that the diforder has ceafed in the weft of Europe, for near a century paft. This happy ex- emption from that horrible calamity has been afcribed to various •. caufes. Many people afcribe it to health laws—a fobjea that has been already difcuffed. Some allege that the ufe of foflil coal has banifhed the plague from London; and Hoffman re- . lates that Halle in Germany, which ufed to be affliaed with malignant fevers, has been free from them fince coal has been , ufed as fuel. Others fuppofe that the great improvements in ; building and in the modes of living, in modern times, have been the means of preventing the return of peftilence. , ; On the firft caufe, I have already given my opinion, and the . reafons on which it is founded. I find no fufficient evidence that ! health laws ever faved a country or city from peftilence, in a , fingle inftance ; but abundant pofitive proof of their utter ineffi- cacy, in a great number of cafes. With refpea to the ufe of coal, we ought not to indulge very fanguine expeaations. It may be true, that violent difeafes be- . came more rare or wholly difappeared, in fome places, about the « time that cpal became of general ufe as fuel. But let us ex- amin faas, and not truft to general curfory obfervations. ' t The digging of coal at New-Caftle for fuel commenced as .. early as the year 1234, as appears by a charter of Henry III. / and.how much earlier, is not known. It was ufed in London \ as early as 1379, in confiderable quantities ; but when firft in- oj troducsd, does not.appear. . In 1550, coal was ia. common ufe 257 In London—its price " twelve fhillings a load." The price fo 1590 was raifed to " nine fhillings a chaldron," which was deemed exorbitant. Thus far we have little light on the fob- jea ; but in 1615, the coal trade occupied four hundred fhips j two hundred of which were employed between London and New- Caftle. The prefent number is five hundred, and London con- tains more than double the inhabitants it did at that time. See Anderfon's Com. vol. 1. and Fleetwood's Chron. Jn 1615 then the ufe of coal muft have been general in Lon? don, and for fome time before, for the growth of the trade mufry have been gradual. But for fifty years after this general ufe of coal, London was affliaed by the plague; the city indeed was rarely free from it, as appears by the bills of mortality, and three times, after that period, the city was ravaged by that dif- temper, as an epidemic, viz. in 1625, 1636 and 1665. So far we have no encouragement to hope for a prevention of the plague by the ufe of coal.- With refpea to the city of Halle, I can fay nothing. The obfervation of Hoffman may be juft, and yet coal may have had no influence in checking the prevalence of peftilence. It belongs to phyficians to afcertain the effea of the vapor from this foflil fubftance on human health. Certain it is, that it occafions inconveniences to thofe who are not. accuftomed to it. So general was the prejudice againft; it, when firft ufed in Lon- don, that in the year 1400, the nobility and citizens petitionee? the king " to prohibit the further ufe of fo noxious and un- healthy a kind of fuel." And. Com. vol. 6. Ap. 935. There is reafon to believe it is not very unhealthy, but I fee no ground to fuppofe it has had the leaft influence in arrefting the progrefs, or preventing the return of the plague. To confirm this opinion, I would mention that the plague difappeared in France and other parjs of Europe, about the time, it did in England ; in Paris, for inftance, where no coal is ufed. In a great part of Europe therefore the fame effea has taken place, without the fuppofed caufe ; which leaves us at liberty tp rejea that caufe. The third reafon afligned for the ceffation of the plague, vi*. Vol. II. I i 258 improvements in building houfes and cities, and in clothing, diet, the ufe of frefh water and the like, is a juft one ; and there can be no rational doubt that thefe alterations have contributed to mitigate the violence and reftrain the progrefs,1 of many acute difeafes. Peftilential epidemics are probably lefs frequent within the laft century, at leaft in the more civilized and commercial parts of Europe, and alfo in America, than they had been in former periods. The poverty, the filth, the dirty, crouded mud cottages, and the feanty fopply of wholefome food, which was the common fare of the peafantry, in Europe, muft have given origin or cur- rency to many difeafes ; and greatly aggravated their feverity. A fample of this may be feen in the early appearance of mortal difeafes in the low narrow ftreets and fmall crouded apartments now occupied by the poorer people in our cities, and the difficulty of expelling a peftilential difeafe from fuch places.* As a general remark it may be alleged with great probability that Europe has derived no fmall benefit, in regard to public health, from the following circumftances. Firft. From the modern improvements in agriculture, by which means many places are dried and fweetened, which ufed to be cold, damp and fetid. Agriculture not only removes, from the earth, fubftances po- fitively noxious to health ; but covers its furface with growing vegetables pofitively falubrious. This is one inftance of multi? * The following extracts will {how the ftate of cities and of man- ners, at the periods mentioned. " Weftminfter and London were once above a mile afunder. The' union with Scotland in 1603, did not a little conduce to make a union of London and Weftminfter; for the Scots greatly multiplying here, ncfted themfelves about the court, fo that the ftrand from the mud walls and' thatched houfs, acquired that perfection of buildings it now poflefles." And. Com. vol, 2. 285. from Hotuel. "Voltaire fays, about the year 1500, " Induftry had not yet changed thofe huts of -wood and plafer, of which Paris was compofed, into fump- tuous palaces. London was ftill worfe built, and peers of the realm carried their wives behind them on horfe-back." In 1504, when James IV. of Scotland was married to Margaret, daughter of Henry VIL of England, the priacefs made her public entry into Edinburgh, riding behind King James on a pillion. Henry's Hifi. Britain, vol. 6. 597. This princely cuftom is ftill preferved in New-England; where the common farmers live in better houfes than many of the nobles, at the period above named. 259 tudes, in the economy of the world, in which the happinefs, com- fort and intereft of man are made to depend on his induftry. See Dr. RufiYs Works, vol. i. p. aj. Secondly. Improvements in building houfes may have con- tributed to the fame falutaray end. The materials are of a kind lefs fufceptible of accumulating and retaining infeaious exhalations, than formerly—the apartments are more fpacious, elevated and airy. Thirdly. Houfes are lefs crouded than in ancient times, as appears by the proclamation of Queen Elizabeth, recited in the foregoing hiftory. In London, one perfon, fince the fire of 1666, is fuppofed to occupy as much fpace as two in the old city. This remark applies efpecially to the poor, who were formerly more numerous than at prefent. Some of the nobles, in the old city, had fpacious gardens, but the mafs of people were miferably poor and crouded into narrow filthy lodgings. Fourthly. There is probably an immenfe difference in regard to general cleanlinefs, between the people even of the fixteenth century, and the prefent age. For this we are partly indebted to commerce, the foarce of wealth and refinement. A more gen- eral ufe of linen and cotton in cloathing, articles which require wafhing frequently, may have contributed to the fame objea. Fifthly. The introduaion of pure water into cities from dif- tant fources, and a liberal ufe of it, in houfes, and the ftreets, have aided in the fame falutary work of diminiftiing the calamities of difeafe. Sixthly. It is believed that the modern diet is more friendly to health than that of former times. It is evident that to this change Europe is much indebted for the difappearance of feorbut- ic complaints, which formerly were epidemic in Holland and other parts, and which ftill prevail in Iceland and Canada, where the poor live moftly on dried or faked fifli, poor flefh meats, with a fmall portion of vegetables. The cultivation of the vine and the orchard has doubtlefs had a confiderable effea. Cider and wine have affiftedin preferving the body from debility in certain peftilential periods j and when temperately ufed, are of excel- lent ufe. 2fJO -Bwl apprehend that the moderns have afcribed too much tti thefe caufes. Any man who will read hiftory with care, will ob- ferve that there has been, within about a century, a confiderable abatement of peftilence in all parts of the world. The plague is fer lefs deftruaive in the Levant, and Egypt, within i5oyeais, than it was in former ages. This mitigation has been cotemporary in all parts of the earth, of which we have any correa knowl- edge. The caufe of this change, I pretend not to affign ; but a fimilar abatement has been obferved in the violence of earthquakes. While I admit however that the true plague has difappeared as an epidemic in many parts of Europe, I do not admit that pefti- lence, in the general fenfe of the word, has wholly difappeared. If the true plagtie, technically fo called, fhould never again occur in London or Paris, I fliould then fay, that improvements in mod- ern times may have mitigated the peftilence, but not that they have wholly banifhed it. Under this word peftilence, I include fmall-pox, anginas and petechial fever, with other malignant diforders, which evidently depend on the fame general caufe as the real plague, operating with lefs force. Thefe difeafes ftill appear in all parts of Europe, and exhibit the exiftence of the pefti' lentialprinciple, altho improvements may have leffened and circum- fcribed its effeas. I do not however confider it as certain that the true plague will not revifitall the weftern parts of Europe. A concurrence of caufes, like that in 1348, might again produce that difeafe in France, England and Ireland, with all its horrors. But the probability is, that the modern improvements have removed fo many of the local caufes of difeafe, that no conftitution of air Will ever again produce the fame mortality, as that under Vorti- gern or that under Edward lit ; nor will the plague ever again be fo frequent, as in former ages. On this point however there is not fufficient ground to build any certain calculations, for the following reafons. Every phy- fician and hiftorian well knows that there have been frequent rev- olutions or changes in the form of certain difeafes—ordinary dif- eafes with new fymptoms, and difeafes before unknown, have Appeared in various countries and in all periods* 2f5i The moft remarkable of thefe are the fmall-pox, venereal dif- eafe, fweating ficknefs, Hungarian fever, petechial fever and ari- gina maligna, with fome of lefs note. I am not about to enter on the great queftion, when or how particular difeafes have been introduced or modified in their fyrap- 'toms. I fufpea however there is a fallacy in the common theory about new difeafes. What are ufually called new are more prob- ably nothing more than the changes that are made in former dif- eafes, by alterations in the atmofphere, climate, habits of living and a multitude Of inferior caufes. The fmall-pox and thfe venereal difeafe feem to have the beft claim to the appellation of new ; yet the fea of their being unknown before the periods af- figned for their appearance, has been juftly called in queftion* See note at the end of this Seaion. Certain difeafes however appear in particular countries, where they had not before been known, fince the date of the earlieft hiftories. Poflibly fome have been propagated by infeaion ; others have evidently arifen from fome general caufe. Thus Pliny relates that the eliphantiafis was brought from Egypt into Italy, by Pompey's troops, but foon difappeared. It is faid alfo that the fame difeafe was propagated in the weft of Europe by the Crufaders. Epidemic feurvy appeared in the maritime parts of Holland in 1556. The petechial fever which defolated Spain in 1557, and afterwards all Europe, was called a new difeafe, different from the ufual purple fever, and faid to be fpread from the iflands of the Levant through Italy to the weft of Europei The angina maligna, in Spain in 1610, was called there a new difeafe ; and in England, where it appeared about fifty years ago, it has been called a new difeafe in that country. But the real ftate of the queftion feems to be, that epidemic difeafes, moft or all of which proceed from qualities of the at- mofphere, fuffer general changes, in conformity with the revo- lutions and alterations which take place in the phyfical world. A remarkable inftance of this, was the fudor anglicus, which was, in its general fymptoms, the plague; but fome general caufe in England firft and afterwards on the continent, fuperadded a peculiar fymptom, that of profufe difcharges by the pores. This charaaer of the difeafe, as has been well obferved by the 2r52 author of Traite de la pefte, was the effe& of a fpecies of revo- lution in the form of peftilence. Infeaion or contagion can have had no concern in producing this phenomenon. The dif- eafe maintained this peculiar charaaer from 1483 to 1551, a period of almoft 70 years, raging occafionally in moft parts of Europe and then difappeared ; at leaft it has never made confid- erable ravages fince that time. This, in medical language, was a new difeafe, as demanding hew modes of treatment; but in the language of philofophy, it Was only a varied form of the fame malady, and proceeding from a common caufe, with the inguinal plague, but that caufe in par- ticular times and places, was modified in its operation. What confirms this idea is, that this fweating difeafe never appeared as an ifolated epidemic, but was always cotemporary with the com- mon plague in other countries—that is, it formed a part of the general effeas of the peftilential principle. Thus in 1483, about the time of its firft occurrence in England, all Europe was defo- lated by the common plague. Denmark loft half its inhabitants, and many other countries fared very little better. The tame may be obferved of its fubfequent returns, and of its prevalence in Ireland, Holland, France and Germany. This is what I call a revolution in peftilence, and it will ap- ply to many other changes in the predominant difeafes of the human race.* Thus the petechial fever, which ravaged Europe ki the fix- teenth century was called a new difeafe ; but I conceive it to "* It aftonifhes me to read in modern books the pofitive afiertions, *• that the.plague is never generated in Great-Britain, or other north- ern latitudes." See Mead, James' Medical Dictionary, Cullen, Ency- clopedia and other original works and compilations without number. Lord Verulam, Sir Thomas Moore, Boyle, Erafmus, Diemerbroeclc and other luminaries of former centuries, who faw the plague frequently in all its varieties, never pretended that the difeafe was not produced in their refpedtive countries. The fudor anglicus, not only appeared frjl in England, but for the firft time of its prevalence was confined to Englifhmen. Yet this was the moft violent and deftru&iveformof the plague that ever has been known. " Nuper novum peftilentia; genus immilit Deus, letiferum fudorem, quod a Britannis extrtum, incredibili celeritate, per orbem longe lateque tlivagatum eft—plurium exitio, furamo tcrrore omnium." Life of Erafmus, 347. How refpeiStable writer* can overlook fuch authorities is to mc in- explicable. have been no more than a varied form of the common purple fever, induced by fome general variation in the elemental caufe of epidemics, or by the feafons. It foimed a part of the pefti- lential feries, and was the precurfor of the plague, as it is to this day, altho it has rarely been fo general or fatal as about the year 1556 andfrorn 1570 to 1576. It is remarkable alfo that the general caufe extended over the Atlantic, and gave the fame charader to the fevers of the Weft- Indies. The difeafe which reduced the forces of Sir Francis Drake at Carthagena, in 1586, was called calenture; a fpecies of malignant fpotted fever. Purchas, vol. 4. n8z. A fimilar fever infeaed the people under Sir Thomas Gates, bound to Virginia, in the beginning of the laft century. And if Ulloa is correa in ftating that the infeaious yellow fever never appeared at Carthagena, till about the year 1730, we have a remarkable proof of a revolution in the difeafes of that climate. We are to conclude from the feas, that the calenture was a diftina form of the peftilesce incident to the country, till the beginning of the prefent century; fince which, it has affumed the charaaer of our bilious plague. I am however inclined to queftion the fea. The true yellow fever has been known in the Englifh iflands from their firft fettlement. It reduced Crom- well's forces when they took Jamaica in 16^. It is further to be obferved that the true form of plague is never known in Spaniih America. But at Quito, and other places, malignant diftempers under the name of fpotted fevers, and pleurifies, fweep away prodigious numbers of people and fall but little fhort of the inguinal plague. Ulloa, vol. 1. 279—a8r. Such then is the peftilence of South-America ; but in other periods, it may take a different form. Thefe obfervations alfo lead to an explanation of the phenom- ena of the angina maligna. It was called a new difeafe in Spain and England, when it firft appeared in 1610; but this is a mif- take. It is evidently defcribed as epidemic a century or two before thofe periods. But the truth is, that form of peftilence had difappeared for a long period and given way to fome other a 64 difbft&' After a time, it re-appeared, perhaps with fome new fymptoms. * The fame remarks apply to the Hungarian fever, the peculiar fymptoms of which firft occurred in the fixteenth century ; and' to a multitude of local and temporary epidemics, which have been Called, on account of fome lingular fymptoms, new difeafes. Thefe feas ferve to explain my idea of the difappearance of the plague in certain parts of Europe. 1 confider the angina maligna as peftilence of the worft kind; and its occurrence in modern times, fince the glandular plague is lefs frequent, may be only one of the revolutions in difeafes of a malignant type, which have marked other periods. The deftruaive force of the peftilential principle, falls principally upon the throat, inftead of the brain or the glands, and moftly upon youth. This may be the principal form of peftilence for a century or two, when it may difappear and give way to the common plague, or to fome new combination of fymptoms, which fhall pafs for a new dif- eafe. A conjeaure of this kind is authorized by feveral changes in the general charaaers of difeafes, at particular periods of the world. I do not therefore confider it to be certain; that the parts of Europe, which have efcaped the plague for a century, are fecure of permanent exemption from that calamity. This conjeaure feems to be authorized by the evident mitiga- tion of the plague in the Levant, within a century. Plagues, it has been before obferved, are obvioufly lefs frequent and lefs fevere, in Egypt and Turkey, than they were in former ages. This remark I believe to be new, but it is a fea ; and this miti- gation correfponds in time with the difappearance of the difeafe in the healthy parts of Europe. From this circumftance, I conclude that this change is the effea of fome general caufe, in the ftate of the elements. This opinion may derive great ftrength, from revolutions or changes in the natural world, analagous to that in the charaaer of epidemic difeafes. It is generally fuppofed by philofophers, that earthquakes are lefs frequent and violent, in modern days, thanin the firft cen- n turies after the Chriftian era, and the imperfea furvey I have 265 taken of their hiftory, gives me reafon to believe the opinion well founded. The eruption of volcanoes is very often fufpended for a long period. Etna was quiet about forty-five years, at the beginning of the prefent century. The volcanic mountain in Teneriffe, which had been quiet ever fince the year 1704, again difcharg- ed its fires in Auguft laft—after a fufpenfion of ninety-four years. There are other volcanic mountains that have flumbered for.ma- ny centuries, as Lipari, near Sicily. The aurora borealis has its revolutions. Sometimes it difap- pears for half a century or more ^ then returns, and frequently . illuminates the heavens. The feafons, on a fmaller fcale, manifeft analagous revolu- tions. At certain periods, we have mild winters ; very little froft and fnow, with foutherly winds, for a feries of years. Then we have a number of long, feverely cold winters in fuece£ fion, with violent tempefts, deep fnow, and perpetual north wef- terly winds. No lefs various are our fummers, as to heat and moifture. The vegetable kingdom exhibits fimilar changes, for which no vifible caufe can be afligned. When our anceftors firft fettled Maffachufetts, they raifed wheat on the eaftern coaft, in the counties of Plymouth, Middlefex and Eflex; but in the year 1664 mildew appeared for the firft time to injure that ufeful arti- cle, and fince that time, it has not been poflible to raife wheat, within a confiderable diftance from the fea fhore. It is related by the French that wheat had not been known to mildew in France, until the year 1550. Van Helmont, p. 1092. In 1770, the potatoe plant, in a particular part of Scotland, was attacked by a difeafe which was new ; and it has fince been fpreading. A fimilar fea is related of the oats in fome parts of the fame country, in 1775. Thefe difeafes, for they are really fuch among vegetables, are new, and as far as they extend, they are a ferious calamity. They are the peftilences incident to veg- etabte life ; which, like difeafes among men, fpring up and dif- appear, without any certain caufes which are within our compre- •Vol.'IL- ■•■-■■ K k 266 henfion. It is cuftomary to afcribe foch phenomena to the fea- fons ; but it would be difficult to find any vifible or comprehenflble qualities in the particular feafons, producing fuch difeafes among vegetables, which had not charaaerized innumerable feafons in former years, which produced no fuch effeas. The death of prim and black thorn in our country, is a fimi- lar phenomenon. Sometimes a new fpecies of tree will fpring up fpontaneoufly arid gradually fpread, where none ever grew before. The pine has thus introduced itfelf into Duxborough in Maffachufetts, within the prefent century. Not twenty years ago, a man was living there who remembered the firft white pine that ever grew in that town : but now one eighth part of the woodland is cov- ered with it. Hift. Cel.vol. 2.5. The animal world difplays fimilar changes and revolutions*- We obferve, not only uncommon numbers of common infeas of fmall animals, in particular years, for which we can aflign n» fpecific caufe ; but we aaually fee certain new fpecies of infeas, and at times, known infeas grow to an uncommon fize. Inftan- ces of the latter phenomenon have occurred in the locufts, in th* frog-kind, and in flies. The flies about Plymouth in 1653, and about New-London, the laft fummer, are defcribed, as being not only diftinguifhable for their numbers, but for their fize. Ancient authors have remarked the feme phenomenon. The millions of worms which fpread over many hundred miles of territory in Americain 1770, can no more be accounted for, than the fudor Anglicus, or any other new form of difeafe. The infea, which about twenty years ago, firft appeared among the wheat, on Staten-Ifland, and which has continued to multi- ply, and effentially injure the crops, over a great extent of coun- try, is unquestionably a non-defcript as to America ; a new form of- animal life. Men are ever fond of propagating conjeaures and vulgar tales for truth. The idle ftony which imported this infea from Germany, and gave it the name of Heflian fly, has been proved, by careful enquiries, to be mere conjeaure ; no fuch animal being known in Germany. Yet it has. laid the founr. dation of a durable error in natural hiftory.- So fond are man- 2^7 kind pf this vulgar prejudice, of imputing all thefc evils to others, that even infeas muft, like plague, be imported ! ' This infea is doubtlefs a new fpecies of animal ; it is one of thofe varieties which nature is continually exhibiting, in the im- menfity of her operations; it is a diftemper incident to that par- ticular plant, and others perhaps in a lefs degree, which, like the fudor anglicus may endure for half a century, and then difappear; or it may be derived, from permanent caufes, and deftined, for a longer time, to annoy that fpecies of vegetable life, like the mildew on the fame plant, on the maritime borders of Maffachu- fetts and New-Hampfhke. The mammoth of Siberia and A- merica, whofe enormous bones are feen in our mufeums, and whofe race is fuppofed to be extina, may be another inftance of perpetual revolution in the works of nature. The lofty pine, the glory of the foreft, covers immenfe traas of our native wildernefs ; but when cut down, is not propagated from the roots or ftump, like moft other trees. Yet I am told that in Carolina, whenever the lands are cleared of the native woods the young growth confifts moftly of pines, tho far from any of that fpecies of tree. Similar changes in the fpecies of trees, are obferved on the clearing of lands in other parts of America. So alfo, on clearing our lands, in every part of America, the foil is foon covered with a full crop of white clover, of fponta- neous origin. Thefe produaions areufually afcribed to the feeds of the plant, feattered by birds, which lie inert, while covered with fhade and leaves, and germinate on the accefs of the folar rays. This folution is conjeaural ; it is, like the importation of the fomes of epidemic difeafes, founded on mere fuppofition ; it is the re- fort of carelefs, fuperficial obfervers, who will not take the pains to extend their views over the works of nature. Do birds con- vey the feeds of pine and of clover and fpread them over hundreds of miles of the wildernefs ? Have thefe feeds been all feattered withina fewyears ? Or will the feeds endure the froft, the ram and the heat of ages, without perifhing or germinating ? Befides, birds feed on the feeds of other graffes and plants, as well as 268 thofe of white clover. Why are thefe not fpead over our woods' in the fame manner ? The phenomena of the forefts in America preclude the prob- ability, or rather the poflibilky of fuch events. The new plants that fpring up, are generated by new powers in the elements, oc- cafioned by different combinations of heat, moifture and air, in- troduced by the labors of man ; combinations which could not exift while the ground was clothed with trees of other fpecies. Plants are furnifhed with feeds for the purpofe of propagation. This wife provifion of a beneficent providence, is highly ufeful to man, and to animals which fubfift on the feeds. But feeds ire not neceffary to the produaion of plants, in all climates. Every vegetable has fome fpot on the globe, where it is indigen- ous, where it was originally produced without feed ; and where it will beft thrive, and grow to the higheft ftate of perfeaion. Such was the origin of moft of the plants now known to man. The principles of animal and vegetable life were cotemporary with the formation of the earth. New fpecies are generated on- ly by thofe gradual alterations vifible in the operations of nature, or by accidental changes, induced by extrinfic and artificial caufes. Animals are alfo produced very often without any parent, but the elements. Hear what is recorded by that accurate obferver, Dr. Lind, on the difeafes of hot climates, p. 208. " It is a phenomenon inconteftibly true, that in ftagnating pools of water at Bombay, produced folely by the rains, and which have no communication with any river or the fea, living fifh are generat- ed ; many perfons have eaten of them. Upon the drying up of the pools, they die and frequently are very offenfive." I have not the leaft doubt of this fea ; and it is on this prin- ciple only that we can account for the exiftence of fifh of various kinds, eels, &c. in brooks and ponds, on the tops of hills, above impaflible falls; and in lakes which have no outlet. And we prove the generation of fuch animals in the places where they exift, not onlybyfheimpraaicabilky of their finding a paffage to fuch fituations ; but by the faa, that many fpecies of. them are never found in fait water, and probably could not exift in it, 269 Any perfon may be convinced of the utter impoffibility of fifhjs making their way to the heads of many fmall ftreams, where they are found, by examining innumerable fuch ftreams on our moun- tains, which are full of trout and other fmall fifh, above perpen- dicular falls among folid rocks, of 50 or 100 feet in height. The truth is, the elements of air and water are fitted to pro- duce animals of the kinds proper to fubfiftin them ; and. fo.are plants. Not a vegetable in the field is found without its worm, its fly or other infea, which it generates or feeds ; and the ani- mal when peculiar to a plant, has the color and the properties of that plant. Not a fpecies of vegetable or animal ^matter, ex- pefed to.a fuitable degree of heat and moifture, which does pot produce its infea. Even living animals are not an exception. Are not the large worms, formed in the human ftomach, pof- feffed of animal life ? And are they produced by a germ depofit- ed by an animal of the fame kind ? Not at all; the fuppofition is ridiculous. They are a difeafe, caufed by the operation of heat and moifture, on fubftances in debilitated ftomachs, which fail to perform the ufual digeftive funaions.* All animals and plants have their difeafes ; and the mildew on wheat, and jthe fear on vines, are probably the effea of the defeaive energies of the elements, and a confequent defeaive procets. in the vegeta- ble funaions ; or of infeas which are the produce of the irregu- „ lar operations of the elements. In the year 1788 a horfe was publicly exhibited in Philadel- phia, with a living animal, of the worm fpecies, in his eye. Set Mufeum, vol. 3. 500. A worm of three inches in circumfer- ence and 20 inches in length was found in the liver of Mrs. Holt of Philadelphia. Ibm. When thefe feas are known and acknowledged, will men ftill be found to deny the doarin of e- quivocal generation ? Worms are often generated in the fmall ul- cers on the furface of the body produced by peftilence. Such is the power ef excitement. All creation is full of thefe varieties. Even the fteUary re- gions exhibit new ftars, either ftationary or revolving, which are * This is the common theory ; fome perfons fuppofe them not a'dif- rafe, but a part of the animal economy, neceffary to full health. Thi« however makes no difference, as to the manner of their produaion. 270 vifible for a longer or fhorter time, and then recede from human view. Other luminous appearances, refembling a lamp, a fpear, a beam, are often obferved, for which we can aflign no caufe. The new ftars may be revolving bodies, which appear to us only in a particular part of thek orbits ; but other Angular celeftial appearances are doubtlefs mere variations in the forms of the ele- ment of fire. The fifh in the ocean are fubjea to the fame revolutionary laws. They often abandon the banks where they have appeared for centuries, and appear in place* where they were never before known. They are fubjea to epidemic maladies, as much as men or cattle ; they often ficken and die, and fometimes it ap- pears that the whole fpecies, frequenting a particular bank, is fuddenly extinguifhed. The changes in the difeafes of men ; all the phenomena of ep- idemics, in their origin and difappearance, their increafed vio- lence and novelty of fymptoms, are the effeas of fimilar altera- tions in the elements which compofe the fyftem. We are but one fpecies of animals, whofe bodies are compofed of the fame materials, and fubjea to the fame laws, as the bodies of all other animals. Animal and vegetable fubftances are alfo compofed of the fame elements, varioufly combined ; they are fimply varie- ties in the forms of matter endowed with life. And the intel- feaual endowments of man, with all his boafted pre-eminence, cannot exempt him from the operation of the general laws which govern every other form or combination of the elements. NoTB, On the Venereal Difeafe. I AM really furprifed to obferve with what pertinacious obfti- nacy, men perfift, in face of the moft inconteftible evidence, upon fathering great evils and calamities on others. The def- cription of Adam's cafting the blame of his fin on Eve, and Eve's charging the whole to Satan, had it been intended to il- luftrate the praaice of tracing difeafes to a foreign country,. could not have been a more exaa reprefentation of the fea, and of the difpofition of men to fhift off, not only crimes, but even moral and political evils, and eaft them on their neighbors. Ev- 1JI try nation and every man conjures up a devil, to which all that. is evil and difhonorable is to be imputed. Pope has well def- cribed this difpofition :— " No creature owns it in the firft degree, But thinks his neighbor farther gone than he ; Even thofe who dwell beneath its very zone, Or never feel the rage or never own." The people in the north of Europe maintain moft ftrenuoufly that the plague never originates in their countries. Mead even affirms that the meafles, as well as fmall-pox, had its origin in Egypt. The inhabitants of Egypt declare that the plague does not originate in their country, but is always imported from the north, as Conftantinople, Smyrna, Greece or Syria ; or from the Bar- bary coaft ; and this filly notion is aaually believed and circulat- ed by moft reputable travellers. The inhabitants of Conftanti- nople, I believe, admit that the plague may originate in that city ; but it is believed by many perfons that this difeafe does not originate there ; and they trace it to Egypt. Many Europeans have adopted this opinion. In Smyrna, Syria, Cyprus, and all parts of Europe, the plague is afcribed to foreigri countries. In Algiers, Fez and all along the Barbary coaft, the plague is held to be imported from Egypt or Conftantinople : It is immaterial which j the great point being to fliift off the origin upon neighbors. Juft fo in America ; it is not admitted by a great portion of people, that the climate can generate a peftilence. The yellow fever which is the plague of the country, is, in popular opinion, always imported from the Weft-Indies. When we go to the Weft-Indies and enquire for the origin of this difeafe, we are told very gravely, that it does not originate there ; it comes from Siam and Bulam ; and books are written by able phyficians to prove the difeafe imported. If then we believe the opinion of the inhabitants of any given country, and their own flory to be juft, we fhall prove that the plague and yellow fever are generated in no country on %7% earth.* There is fomething extremely laughable in thefe feas ; but to philofophy, to medical fcience and national candor, they are as difgraceful as they are prejudicial. My enquiry into the hiftories of thefe difeafes, has demonftrated to my mind, that moft peftilential difeafes have originated, where they exifted ; and no one of them will fpread or exift long, in an atmofphere in which it will not originate. The fmall-pox does not ufually fpread without infeaion 4 but I can prove, by many inftances, that it does originate, in fpo- radic cafes, without infeaion. In South-America, it fpreads and becomes epidemic, in certain periods, then totally difappears. Ulloa, book 6. The venereal difeafe appears to be propagated folely by infec- tion. It muft however have originated at firft without infeaicn j and may ftill, for aught we know, originate in the fame manner. But the attempt of phyficians to palm this difeafe on the na- tives of America, is a moft grofs and abominable attack on truth, perfevered in againft the plaineft and moft indubitable evidence. In the annals of England, there is the cleareft proof of the exiftence of that difeafe, in the twelfth century ; and it was the fubjea of legal provifions as early as the year 1162, which laws are ftill extant, and were then only a renewal of thofe which were Jlill more ancient. In the records of the Lordfhip of Winchefter, there arc many regulations refpeaing the ftews which were authorized to be kept in Southwark; one of which exprefsly prohibits any " ftew-holder to keep any woman, that hath the perilous infir- mity of (Brenning) burning.^ In a book written from a manufcript about 1430, in poffeflion of the bifhop of Winchefter, one article begins thus; " de his qui cuftodiunt mulieres habentes nephaadam infirmitatem ;" it * " But where the extreme of vice was ne'er agreed ; Afk where's the north ? at York, 'tis on the Tweed; In Scotland, at the Orcades; and there, At Greenland, Zembla, or the Lord knows where." EJfay on Man, 11. 221. f Burning is a modern orthography ; the ancient was brent, brenmng. So Chaucer wrote it. Canterbury Tales, »4»7, and in other pafTages. " The fires brent upon the auter bright, That it gan all the temple for to light." 273 goes on " item, That no ftew-holder keep noo woman wythid his hous that hath any ficknefs of brennlng, but that fhe be put out, upon the peyne of make it a fyne into the Lord of a hun- dred fhylings." That this was a common difeafe appears from the frequent mention of it in thofe records ; and that it was the fame difeafe, now called venereal, appears from the defcription of it given by Arden, phyfician to Richard II. and Henry IV. between 1377 and 1413; who fpeaks of it as a "certain inward heat and excoriation of the urethra." This difeafe was called a burning and* went by that name, till the middle of the 16jh century. See Philofophical Tranfaetions, No. Z51- Baddam's Memoits, vol. 6. 390. .It is afferted by European authors that this difeafe was preva- lent among the natives of America, when the Spaniards firft vifited the country. I cannot controvert the aflertion, for I do not poffefs the original Spanifh hiftories of their firft voyages. But it is poflible this may have been true. It is fomewhat ftrange however, if that difeafe was formerly very prevalent among the natives, that in modern times, it fhould hardly be known among them. Ulloa, in his voyage to South-America, book 6, declares that the " venereal diftemper is feldom known among the na- tives;;" akho fo common among the Spaniards as to have loft the infamy attached to it in other countries.* See alfo book 5. ch. 6. The fmall-pox has been fuppofed to have originated in Egypt * Thefe remarks on the origin of difeafes proceed folely from my love of auth and found philolbphy. I am no more anxious to exone- rate the favages of America from the charge of communicating the luts venerea to Europeans; than I am to vindicate Egypt from the, charge of originating all the plagues that have defolated Europe. It is my wifli to proftrate that fyftem of error refpecling the origin of pefti- lential difeafes, which difgraces modern days. _ _ The following rtmark is of lefs confequence. The Britifh DicShon- arits define t^e word Buccaniers by " Pirates of America or American Pirate." But names lead to error. The buccaniers were all origin- ally Europeans, french and Englifli, who committed piracies in the Weft-Indies and Spanifh America. Encyclopedia art. Buccanier. Thus the name " Heffiau fly" given in this country to a mifchievous infecT, .w the offspring of ignorance and the parent of a material error in common opinion. Vol. U. LI *74 Or Arabia, and to have been propagated over the world by fpe- cific contagion. But the fmall-pox, altho we know not the time or place of its firft appearance, is only a new form of that clafs of difeafes called, exanthemata, or eruptive. It is the produce of a revolution in difeafe, and now originates any where and every where, without contagion. With refpea "to the origin of the lues venerea, we are left in the dark, as we are with refpea to the fmall-pox. It is agreed on all hands that none of the Greek and Roman writers on med- icin, have defcribed the difeafe. But there is not a thadow of doubt that a fpecies of this difeafe exifted in England as early as the Norman conqueft; and probably in the other countries of Europe. Not a medical work of that period, if any was writ- ten in the weft of Europe, has furvived the ravages of time ; and we are indebted to the legal eftablifhment of ftews in South- wark, for the evidence of the exiftence of that difeafe, It is however not at all improbable that about the year 1496, this difeafe might have acquired fome new and malignant fymp- toms, and fpread with a fatal rapidity, that might alarm man- kind and render the diftemper more an objea of notice. An- tecedent to that period, it might have been much more mild and lefs deftruaive. This idea is greatly ftrengthened by the known faa that other difeafes had, about the fame time undergone fimi- lar changes. It was but about ten years before, that the plague took the fweatlng form—an event as novel, as the generation of a new difeafe. What is more remarkable ; in the very year afligned for the appearance of the lues venerea, an epidemic lep- rofy overran Germany ; an event equally novel. Thefe feas confirm my ideas of certain revolutions in the fymptoms of dif- eafes, correfponding with material changes in climate or modes of life. *75 CONCLUSION, Addreffed to the learned Societies, in America, Europe and Afia. JL HE preceding hiftory of Epidemic difeafes was undertaken folely from a defire of inveftigating the truth, refpeaing the ori- gin and phenomena of thefe terrible feourges of the human race-. When the peftilence appeared in the United States in 1791 and 93, I had not afufpicion that the popular doarins refpeaing con- tagion, are not well founded. The frequent recurrence of the difeafe in fubfequent years, in oppofition to all the beft efforts of health officers, in executing rigid laws of quarantine, had, in 1795, fhaken my confidence in thofe doarins. Myinveftigations in that and the next year, convinced me that the peftilential fever Which has vifited fo many parts of America, is generated in the country ; but ftill I had not the leaft fufpicion of a cormeaion be- tween epidemic difeafes. The inveftigations of the year paft, have refuked in unfolding principles and feas to me altogether new and furprlflng ; they cannot therefore be afcribed to a with to eftablifh a preconceived theory. Thefe refultsnot only confirm my fufpicions that the peftilence r5f America is of domeftic origin, but they overthrow the pre- conceived fyftem of the origin of peftilence, in temperate lati- tudes, from fomes conveyed to thofe climates from fouthern re- gions ; and demonftrate that it originates occafionally in all lat- itudes from the 25th to the 65th. It is demonftrated that peftilence, in temperate latitudes, is never an ifolated epidemic, but the crifis of a feries of epidemics ; and we are furnifhed with the means of determining unequivo- cally the charaaer of peftilence in every cafe, on the following fimple, principles. " If, on the appearance of peftilence in a particular place, all 27G other difeafes ceafe, or take fome of its predominant fymptoms., that peftilence is generated in that place, and dependent on the ftate of the elements." It is impoffible, on phyfical laws, that this criterion fhould ever fail. Another criterion, almoft infallible, is the prevalence of cer- tain difeafes before and after the peftilence. If peftilence is im- mediately preceded by meafles, affeaions of the throat, inflam- matory or typhus fevers with anomalous fymptoms, and efpecially by catarrh, that peftilence is an epidemic, produced on the fpot, and only the autumnal form of difeafe—the other difeafes, prece- ding and following, being the vernal and hybernal forms, produ- ced by the fame general principle. Of the peftilences which afflia mankind, in all climates, an jmmenfe proportion, probably nineteen twentieths, belong te this fpecies—they are epidemics, beginning and ending at the com- mand of the elements, under the co-operating influence of fea- fons and local caufes. Thefe epidemic peftilences are more or lefs infeaious, accord- ing to their violence, or the places where they exift. In clofe rooms and narrow alleys they are dangerous ; hence their mor- tality in fleets, camps, jails, and particular parts of cities. But the infeaion of fuch difeafes extends to the diftance of a few feet only, and is capable of diflipation in a free air, fo as to reduce the danger of attending the fick almoft to nothing. The fame is true of difeafes of mere infeaion, not epidemic. Difeafes, dependent on infeaion only, are fometimes introdu- ced into cities and hofpitals, and occafion confiderable mortality. But they are propagated by contaa or near approach only, and do not affea the charaaer of other difeafes current in the place. The confequence refulting from thefe principles is, that epi- demic peftilence is not under human control—but difeafes propa- gated by mere infeaion may be arretted and fubdued. The only means of avoiding or mitigating epidemic peftilence are firft to withdraw the aid of local caufes ; fecondly to fit the ' body, by modes of living, to refift its caufes—and thirdly,'on failure of thefe, to remove from the place where its exifts, • %77 The infeaion of all difeafes, even thofe of fpecific contagion, as fmall-pox and meafles, may be avoided by keeping at a dtf* tance from the difeafed. The infeaion of difeafes not fpecifi- cally contagious, as plague, yellow-fever, dyfentery and jail fe- ver, may be nearly deftroyed by free air, and cleanlinefs. With refpea to the primary caufes of epidemic difeafes, we are in the dark ; but we are certain, from all hiftory and modern obfervations, that the caufes of epidemic difeafes among the hu- man race, affea every fpecies of animal and vegetable life. The opinions which I have fuggefted concerning the general caufe, feem to have a foundation in the coincidence of epidemic difeafes with numerous efearical phenomena. At the fame time, the reader will confider thefe opinions rather as conjeSural, than pqfitlve. No certain conclufions can be drawn from an in- terrupted and imperfea feries of feas. More materials are ne- ceffary to enable us to erea a theory of epidemics which (hall de- ferve full confidence. The common doarin of contagion 13 utterly infufficient and unphilofophical ; for if admitted, it never leads us nearer to the caufe. If we trace the yellow fever to the Weft-Indies, and the plague to Egypt or Conftantinople, we are not an inch nearer to the fource ; for thefe difeafes are not always to be found in thofe countries ; and the people there are as much puz- zled to find the fource of them, as the people of Great Britain or America. If we trace thefe difeafes to the coaft of Africa, or to Siam, we are as diftant as ever from the fource; for many times, the difeafes are not to be found in thofe countries, and feldom in- deed are they ever found within the tropics, except among for^ eigners. Indeed nothing is more common than for the yellow fever to be imported into the Wefl-Indies in veffels from the United States. When veffels from northern latitudes have long paffages, it of- ten happens that feamen are feized with the difeafe, before they arrive at the iflands ; and the Weft-Indians may often allege the difeafe to be imported in fuch veffels, when it does not exift in the. United States, 2;8 In fhort, the doarin of deriving all peftilential difeafes from contagion or infeaion, were it not for the rmmenfe mifchief it does to fociety, would not deferve a ferious refutation. Infec- tion is zfubordinate caufe of the propagating of malignant diftem- pers ; but is itfelf an effecl of feme more general caufe, whole force is. a hundred fold more powerful and formidable than that of infeaaon. I have, in condefeenfion to popular opinion, ftated the evidence of the domeftic origin of the bilious plague, as it ftands on the arrival or non-arrival of veffels, and other feas. of that kind. But I really confider all this evidence as trifling, when compared with the phenomena of the difeafe itfelf and ks-precsrfors and attendants. The uniform appearance of other epidemics, as introduaory to peftilence, and manifefting an effential change in the atmofphere, with the numerous ac- companiments of the plague and yellow fever, amounts to evi- dence of domeftic origin, which leaves no room for cavil or controverfy. For the purpofe of colfeaing feas, the only fafe foundation of principles, and comparing the phenomena of difeafes and the elements, which occur nearly at the fame time, in different coun- tries, I fincerely with and requeft that all medical and philo- fophical focieties would undertake to regifter feas and recipro- cally to communicate them, by means of a general correfpond- ence. The feas to be regiftered might be comprized uader the following heads. The time of the appearance and difappearance of any epi- demic difeafe, with its general hiftory. The places where it firft occurs to be defcribecU in regard to land and water, height of the land, conftruaion of the city or ftreets, pofition as to points of compafs, woods, moraffes, &c. The claffes of people moft generally affeaed. The general ftate of the feafons, as to heat, and cold, drouth and moifture. The time of earthquakes, meteors, lumen boreale, and all lingular celeftial appearances—with unufual tempefts, efpecially when accompanied with hail—all compared with the lunar phe- nomena. 279 The appearance of unufual infeas of all kinds, and any ck- cnmftance attending them. Difeafes among cattle, fheep and other animals. Sicknefs and death of fifh of all kinds. Volcanic eruptions, with the phenomena preceding, attending and following them. For the purpofe of afcertaining the lunar influence on the hu- man body, or any diurnal influence, it would be defirable that medical gentlemen fhould note the days and the hours of the day when perfons are feized with particular difeafes—efpecially epidemics—the hours of exacerbation and of paroxifms in fever— the hours which are moft fatal to the difeafed—and the time when convalefcents are moft apt to relapfe.—Thefe feas fhould be compared with the pofition of the moon, in her orbit, and ef- pecially in regard to her perigee and apogee; conjunaion and op- pofition ; as alfo with the tides in the main ocean.* Should the principles unfolded in the preceding work prove to be well founded, they will lead to many important praaical in- ferences. I. If peftilential fevers never appear in the temperate latitudes^ without certain precurfors, men will, with careful obfervations, be enabled to forefee the danger and prepare for it ; or to ufe un- common diligence in removing the fubordinate local caufes. II. If in certain years peftilential fevers are more predominant, than in others ; and the condition of the elements fitted to pro- ducediem, is univerfal over fea and land, the fea is of no fmall moment in maritime affaks. Double precautions will be taken in fleets, and in merchantmen bound on long voyages. III. If peftilence is progreflive and firft manifefted in certain malignant fevers, the fea may be of great utility to large cities. The approach may be perceived in time to fave the inhabitants by flight, if not by other precautions. v IV. If no plague or yellow fever ever appeared in temperate climates, unlefs announced by other diftempers, the magiftracy may be enabled to diftinguifli when there is danger, and when * The time of high and low water in rivers and bays may not be the true time, in the open fea—or of the greateft and leaft influence of the moon. 28o not; and may avoid innumerable vexations to commerce, arifing from the rigid execution of health laws, when there is not the leaft occafion. V. But a moft important ufe to be made of the feas here col- feaed, will be, to guard public health from the ill effeas of bad provifions. If, in peftilential periods, fait is Jefs efficacious in preferving flefh, and by means of a greater fermentation of the juices, fifh and flefh are more readily diffblved by a putre- feaive procefs, more caution will be found neceffary in packing and repacking them, and more care to avoid ufing it in a bad ftate. If the effluvia of diffolving flefh and vegetables are more poi- fonous and prejudicial to health at fome times, than at others, it is of importance that, on every fuch occafion, early notice fliould be given of the danger. If animals, which conftitute a part of the food of men, are fubjea to epidemic diftempers, they cannot be eaten with fafety, while affeaed by difeafe. When fifh or fowls are fickly and many of them die, or become lean, the faa fhould be afcertained by-the faculty or a board of health, and public notice fhould be given, that people might avoid ufing them as food. In fome inftances, fifh are fo fickly as to excite naufea ; in which cafe the ufe of them fhould be forbidden. I will clofe this treatife with the following reffeaions. In the conftruaion of the univerfe, we obferve every part of the fyftem to be governed by uniform laws, adapted, with infi- nite flcill, to preferve harmony and order. Limited as our un- derftandings are, we can difcover many of thefe laws, v/hich are calculated to imprefs on our minds the moft fublime ideas of the univerfal intelligence and wifdom of their Great Author. The exiftence of natural and moral evils has led feeptics to queftion the perfeaions of the author of nature. But doubts on this fubjea argue want of knowlege or want of candor. It is extremely evident that all the neceffary evils of the fyftem are calculated to produce good. The operation of that univerfal principle of light, heat and fire, which pervades our fyftem, and which is inceffantly compounding and decompounding the other more fluggifh materials of the earth and atmofphere, aje effen? 28i tial to the viciflitudes of the feafons, rain, fnow, hail and dew, which are neceffary to preferve the principles of animal and vegetable life. Storms, hurricanes, earthquakes and volcanic eruptions, however inconvenient to men at particular times and places, are among the means of giving to the principles of life, more equal diftribution, and of renewing their energies. Epidemic difeafes are fome of the neceffary effeas of the gen- eral laws that govern the univerfe. But they have alfo a final caufe of immenfe value to the human race. They are deftined and calculated to anfwer moft important moral and religious purpofes. Men, with their prefent nature, under a conftant courfe of profperity, would degenerate into devils or brutes. Uninter- rupted eafe and quiet contraa the heart and fteel it againft emo- tions of fenfibility—the man rufhes into vices and crimes, or finks into floth. So often have I feen the hearts of men depraved and their moral charaaer debafed, by fudden profperity, that I am perfuaded the world, without frequent infliaions of pain and diftrefs, would not be habitable. The natural evils that furround us, intermingled with innumerable blelfings, preferve the mind in perpetual vigor, in feeking the means of proteaion ; they lay the foundation for the exercife of the fineft feelings of the human heart, compaffion and benevolence, which are the fources of focial virtue ; they humble the pride and arrogance of man, by cre- ating in his mind a perpetual dependance on divine power ; in fhort, they create and preferve that fenfe of obligation and ac- countability to God which is the germ of piety, and moral ex- cellence. Vol. II. Mm 282 ADDENDA. Of the Lunar Influence. JL T is a well known fea that the moon has a great influence on the elements of this globe, the effeas of which are very vifible in the viciflitudes of weather. This influence is fuppofed to be the principal regulator of the tides, and the efficient caufe of the changes in the atmofphere, which produce rain, hail, fhow and wind. It is believed alfo to affea the growth of plants, and Pliny, followed by St. Pierre, alleges that the lunar rays diffblve fnow and ice. Popular opinion confiders the moon as exerting a powerful influence on animal fubftances, and it is an incontrover- tible fea that its beams accelerate the putrefaaion of flefh and fifh. Fifhermen and tailors can all atteft this fea, and it coincides with what Pliny afferts. Nat. Hift. lib. 2. ioi. " Id man- ifeftum cffe, quod ferarum occifa corpora in tabem vifo fuo refol- vat."* Moon light diflblves or corrupts the flefh of animals that are killed ; it renders found fifli foft in a few hours, and fifhermen are careful to cover from its rays the fifh they have caught. It probably aas upon flefh byjtimilus, exciting a fermentation in the juices. The Newtonian theory of tides, which explains the phenom- ena by lunar attraaion, has been recently called in queftion and warmly oppofed by the ingenious St. Pierre, in his ftudies of na- ture, who fubftitutes a fchcme of his own, which afcribes the tides to the diurnal effufions of the polar ices. I am charmed with the writings of St. Pierre, which have opened a * St. Pierre affirms that the moon melts ice, and relies on the pafTage of Pliny in the chapter cited, " glaciem refundat"—but it is queftionable whether the pafTage will bear that conftruction ; and if it will, the af- fertion of Pliny is not fupported by modern obfervations. See Studies of Nature, Vol. i. Expl. of the plates, p. 69. Ice is diminifhed by evaporation in moon light, without forming water, 283 new and entertaining volume of the works ©f nature. But his theory of tides feems to manifeft none of that ingenuity, which is confpicuous in other parts of his writings, and is utterly un- fatisfaaory. In the firft place, during fix months or more, in each polar region, no fnow or ice is melted, unlefs by the moon. The fun is below the horizon, and the moon's influence, if it diffolves fnow and ice according to Pliny, evaporates all the water pro- duced. This is a fea that accords with modern experiments, that ice in the night, however cold, lofes apart of its weight, bat it is by infenfible evaporation. To remove this difficulty, St. Pierre fuppofes the tides in one polar region to be the effea of the melting of fnow and ice, in the oppofite polar regions. But to this hypothefis we may oppofe an infuperable ebjeaion, derived from the great and univerfal laws of equilibrium, obferved by water. A diurnal wave or ele- vation would inevitahly fubfide into a level, before it could reach the equator, or even the temperate latitudes. Befides the Atlan- tic is of very various breadth, in different latitudes. Between the coaft of Brazil and Terra Firma on one fide and Africa on the other, the breadth is fcarcely half as great, as in the latitude of 25 deg. north. A diurnal wave compreffed and dilated, in thefe different fituations, muft exhibit the tides in one place, twice as high as in another ; but in the regions mentioned, this is not the faa. There are many of the phenomena of the tides which cannot be explained on St. Pierre's hypothefis ; but the foregoing re- marks are fufficient for my prefent purpofe. The tides doubtlefs depend on lunar and folar influence ; but the phenomena cannot be folved on the common theory of attraction. In this refpea, I am confident the Newtonian' theory, as explained by Kepler and others, is as inadequate, as that of St. Pierre. The latter author has enumerated fome infuperable objeaions to that theory, to which the reader is referred. But I have other obfervations to make on this fubjea, which are probably new. The manner in which aftronomers have attempted to explain the oppofite tides, is as follows. " The power of gravity dimin- ifhes as the fquare of the diftance increafes—therefore the waters 284 en {he fide of the earth next to the moon, are more attracted than the central parts of the earth ; and the central parts are more aftraaed by the moon than the waters on the oppofite fide of the earth—therefore the diftance between the earth's center and the waters on its furface, under and oppofite to the moon, will be increafed. The earth by its gravity falls towards the moon —-•the water direaly below the moon rifes and fwells towards her" —-the water on the oppofite fide recedes from the center and ri- fes—or ftrialy fpeaking, the center recedes from the water. On the fides of the earth between the points under and oppofite to the moon, the water is depreffed and falls below the former level." See Fergufons's Aftronany, on the Tides, and Encyclopedia, Art. Aftronomy, 363. As I am not about engaging in aftronomical or mathematical calculations, I fhall content myfelf with ftating thefe general prin- ciples of Newton, Kepler, and later aftronomers, with a few objeaions. I. This theory does not explain, in a fatisfeaory manner, the reafon why there are no tides in lakes and Mediterranean feas. If the principle is juft, that the earth recedes from the water oppofite to the moon, leaving the furface of it at a greater dif- tance from the center, why, when the Euxine or Mediterranean is oppofite to the moon, does not the earth beneath thefe feas, re- cede from their waters, as well as from the waters of the ocean, in the fame longitude ? The earth confifts of folid fubftances, and by the laws of attraaion, muft, in all its parts, be moved equal- ly, under the fame circumftances of diftance from the attraaing body and denfity, or folid contents. To fuppofe the earth, when covered by an ocean, to be attraaed by the moon, and not when covered by a lake or arm of the ocean, is, in my view, neither logic nor philofophy. Nor is the reafon afligned for the defea of tides in lakes and feas, on the fide next to the moon, in the leaft fatisfeaory. It is found in the Encyclopedia in thefe words. " There are no tides in lakes becaufe they are generally fo fmall, that when the moon is vertical the attraas every part of them alike, and therefore by rendering all the water equally light, no part of it can be raifed higher than another." 28^ But this explanation does not meet the difficulty. The New> tonian theory ftands on the hypothefis that the waters on the fide of the earth next to the moon, are more ftrongly attraaed than. the adjacent land ; therefore they rife above feveral feet of the earth. But the folution above recited does not reach this point j for the waters of the ocean rife higher than the contiguous earth ;. but the waters of lakes always obferve the fame relative altitude on their fhores. If then the moon attraas the waters of lakes at all, or occafions them to rife, it attraas the adjoining earth and raifes it in the fame degree as the waters ; but in regard to the ocean, it attraas the water and leaves the contiguous earth behind. In fhort, if attraaion and gravity have uniform laws, as we muft believe they have, the attraaion of the moon will not account for tides in the ocean, while there are none in lakes and inland feas. II. If the moon's attraaion is the caufe of tides, why is its force much lefs in the equatorial regions, than in the diftant parts of the globe ? It is a well known fea, that the tides within the tropics are very fmall, and that they are more con- fiderable as we recede from the equator towards the poles. This is contrary to what ought to be the cafe, on the principles of at- traaion ; for on the Newtonian theory of gravity, the higheft tides fhould be on the parts of the earth neareft to the moon. The reverfe of this is the cafe, and the circumpolar regions of the earth have the higheft tides. The tides within the tropics are from 12 to 24 inches—in the latitude of Greenland, al- moft as many feet. III. The theory of Newton is not reconcileable with his own principles of gravity, which fuppofe the force of it to be equal to the quantity of matter contained in bodies. Now the theory implies that on the fide of the earth next to the moon, the water is attraaed more than the earth ; but on the oppofite fide, lefs. This cannot be folved on the principle of diftance ; for this is too fmall to account for a hundredth part of the effea. Indeed the water and the land on the fhore, may be confidered as at the fame diftance. Nor can it be folved on the principle of a difference in the quantity of matter, in earth and water. If the earth, having 286 more denfity and matter, is moft attraaed, the principle muft aa uniformly on both fides of the earth—on both fides, the earth muft move towards the moon further than the water, which is contrary to fea. If the water has moft matter, the fame principle muft govern it on both fides of the earth, and move it fartheft towards the moon. But here the principles of cohefion interfere with all thefe deduaions. Thefe principles are fo powerful, as to overcome the attraaion of a diftant body, nor is it to be fuppofed that the power of the moon overcomes the force of cohefion, and by attraaing the parts of the earth next to it more than the parts on the oppofite fide, changes the form of the earth from a fphere to a fpheroid. It is not fuppofed that the whole folid mafs of the earth is continually changing its figure by means of lunar attrac- tion. If fo,' this figure muft be rotatory. The theory then fuppofes that on the fide next to the moon, the water is moft ftrongly attraaed and rifes above the earth— but on the fide oppofite, it is attraaed lefs than the earth. The folid globe is moved towards the moon, and the water left lag- ging behind ! What is more lingular, the earth near the equa- tor, on the fide oppofite, is drawn only two feet further towards the moon than the water, or perhaps but one foot; while in the temperate latitudes, it is drawn fix or eight feet, and in the lat- itudes of 60 and 70 degrees, fifteen, eighteen, and twenty-five feet further than the water. This may be philofophy, but to me it is utterly unintelligible ! Nothing is a more ferious misfortune to fcience, than the er- rors of a great man. Moft of mankind take principles and feas upon truft, and defend them with a zeal proportioned to their confidence in the man who has publithed them. I revere the charaaer of Newton, of Kepler and of Haller ; but this vene- ration does not in the leaft incline me to receive their doarins without being convinced that they are well founded. After moft careful inveftigation, I am fatisfied, that the principles of at- traaion, will not account for the tides oppofite to the moon, nor for the difference between the height of the tides in differ- 287 ent latitudes. Yet I have not the leaft doubt, that moft of the phenomena of tides are regulated by the moon. If I was afked, on what principles the tides depend, my an-. fwer would be, / do not know. But numerous feas, all con- curring to the fame point, lead me to fufpetl the vibrations of the ocean to depend on elearicky, influenced by the moon, the fun, or other diftant orbs, and aaing by repulfion as well as at- traaion ; or by increafing and diminifhing the elafticky of the water. In the firft place, it is agreed among philofophers, that the air, when free from vapor, is an dearie ;• that when cold, k is moft efearic, and when heated, it becomes a conduaor ; and confequently that the atmofphere in the torrid zone is always in a conduaing ftate, while the air of the northern regions, if clear, is an efearic. In fhort, it is agreed that the atmofphere of the temperate and frigid zones contains more elearicky, than that of the torrid zone. Thefe feas correfpond with the phenomena of tides. In the regions, where there is the leaft elearicky, there is the leaft intumefcence of the ocean—thofe are the equatorial regions. There, the temperature of the air alfo fuftains very fmall varia- tions ; fo does the height of the ocean. As we recede from the equator cold and elearicky increafe ; fo does the elevation of the tides. Again, the fame train of phenomena attend the barometer. Within the tropics, the variations of the mercury in this in- ftrument, are very fmall; but in the temperate and cold regions, they are more confiderable, and increafe as we recede from a warm to a cold and efearic atmofphere. Similar phenomena attend the twilight. Within the tropics, the twilight is of much lefs duration, than in cold regions. " Heat, fay philofophers, diminifhes the air's refraaive power and denfity, and cold increafes both. The horizontal refrac- tions are near one third lefs at the equator, than at Paris." Fergufon's Aftron. 97. The denfity of the atmofphere, within the tropics, may be lefs than at the polar circle ; but the weight is nearly the fame, the barometer being in general as high at the equator, as in north- 288 ern latitudes. But the air, in hot climates, has lefs powers of refraaion; that is, there is more power of refraaion in an at- mofphere that is moft perfealy efearic, or that contains moft elearicky. It is remarkable alfo that, in equatorial climates, the atmof- phere exhibits no vifible ftreams of elearicky ; as it does in the polar circles. I know not how far this parallel may be extended; but there is a furprifing refemblance between all thefe phenomena. In general then we obferve that in the equatorial regions, the den- fity, weight, elafticity and temperature of the atmofphere, are more nearly uniform, than in northern climates ; and the eleva- tion of the ocean in tides correfponds with this uniformity. A* We recede from the equator, the variations of the atmofphere increafe, and fo do the variations in the height and depretEon of the water. From thefe phenomena a fufpicion arifes, that the medium by which the moon and fun aa upon the ocean, is the efearical fluid ; as their influence appears to be in proportion to the elec- tricity of the atmofphere. Hence the higheft tides at a diftance from the equator, where the heat and cold and elafticity of the air are fubjea to great variations. By what law, it will be aflced, is this effea produced ? I readily confefs my ignorance. But the phenomena of oppofite tides feem to bear a great affinity to the well known laws of elearicky, attraaion and repulfton, and a pofttive and negative ftate. I pretend not to* account for the phenomena, for I am perfuaded that the experiments on elearicky which man is ca- pable of making, will never unfold all its properties, nor explain all the laws by which this energy of nature is exerted in the government of the material fyftem. But the influence of the planets on the elements of this globe has, in all ages, been a fobjea of belief or of derifion; and furely it is a fubjea in phyfics much more intereftkig to man, than many fpeculative queftions which cannot affea his health and happinefs, but which occupy the labors of inveftigating minds. I will therefore throw together a few obfervations 289 which may afford light on the fubjea ; or at leaft may excite'a foirit of enquiry. In the firft place, it is generally known and admitted that the influence of the fun and moon upon this globe are in proportion to their proximity. The higheft tides are when the moon is in her perigee, and in conjunaion with the fun, and efpecially when the earth is in her perihelion, or neareft to the fun. But the moon exerts more than ufual influence on the atmofphere, in Other pofitions. Her power is grcateft in her perigee and apo- gee, and in her conjunaion and oppofition to the fun. Her in- fluence on the tides, under the combined and feparate operations 6f thefe circumftances, has been fully illuftrated. But her in- fluence on vegetation, on the viciflitudes of weather, on health, and the phenomena of the ekarical fluid in earthquakes and Volcanic eruptions, feems to have paffed unobferved, or at leaft, to have never been reduced to any thing like fyftem. One of the moft ftriking effeas of lunar influence, is obferv- able in earthquakes, which ufually happen near the time of the moon's perigee or apogee, conjunaion or oppofition. As this fea feems to have efcaped obfervation, I will here infert proof of it. The great earthquake which demolifhed Lima on the 28th day of Oaober 1746, happened fix hours before the full moon, and the day before her apogee. That which deftroyed Lifbon Nov. 1, 1755, was three days before the change and four before her perigee. The great fhock in America on the 18th of the fame month was a few hours after the full moon, on the day of her apogee." The great earthquake in America on the 2d of June O. S. 1638 was on the day after the new moon and near her perigee. [Some accounts place this on the firft of the month, in which cafe it was the fame day with the change.] The fhock which convulfed America, and demolifhed moun- tains in Canada January 26th O. S. 1663, was on the day pre- ceding the new moon. The great earthquake in South-America, June 3d O. S. 1744 was four days after the new moon. Vol. II. N n 290 The memorable earthquake in North-America on the 29th of OaoberO. S. 1727, was about three days before the new moon, but on the day of her perigee. The fhock in America on the 29th of November 1783, was pn the day after the moon's perigee. That on the 16th of May 1791, was on the day of her peri- gee and one day before the full moon. The fhock on the ift of November 1761, was the day before her apogee. The great earthquake fo Iceland on the 10th of July 1789, was on the day of her apogee, and three days after the full. That in Tufcany on the 30th of September in the fame year, was two days before her apogee, approaching the full. A fhock at Lifbon on the 27th of November 1791, was two days after her perigee and change. A fhock on the 15th of January 1791 in Virginia, was two days after her apogee, and approaching the full.* Thefe two laft inftances, according to another almanac, hap- pened one day after the perigee and apogee. I have not taken pains to enter into exaa calculations of the moon's place, as I do not deem it material. It is fufficient for my purpofe that almoft all earthquakes happen near the time of the moon's conjunaion and oppofition, or her perigee and apogee. Of thefe pofitions, it is obvious that her perigee and apogee have much the moft in- fluence ; aud the inftances I have examined are almoft equally divided between thefe two pofitions. Of all the earthquakes which I have compared with the moon's place, one or two only fall in her quadratures, and at her mean diftance from the earth. An inftance happened on the nth of April 1799 in Carolina. I have compared feveral other inftances, which happened near the perigee and apogee, but it is unneceflary to fpecify them. The examples mentioned will eftablifli the generality of the fea, and the foundnefs of the principle. On the principles of attraaion, it will readily be admitted that the proximity of the moon to the earth, at certain periods of her * A fevere earthquake in the weft aud north of France on the zyth of January of the prefent year, 1799, was a few hours after the moon's perigee. : • Spi revolution, muft draw, or excite into aaion and difcharge, the elearicky, of the earth. This accounts for earthquakes during the moon's perigee. But on enquiry we find a great proportion of the fhocks take place durihg her apogee, when her diftance is greateft and her fuppofed power the leaft ; and riot only fo, but during her oppofition to the fun, when her diminifhed influ- ence is fuppofed to be counteraaed and ftill further dimlnlfhedhy the attraaion of the fun. This is ah important fea and deferves inveftigation. That the influence of the moon is the direa ex- citing caufe of earthquakes, can hardly be queftioned, after ef- tablifhing the fea, that four out of five, or a much larger pro- portion, happen when the is in particular parts of her orbit ; but why her greateft diftance and her leaft, fhould produce exaaly the fame effeas, a fea equally well eftablifhed, is a queftion which can perhaps be folved only on ekarical principles. That the elearicky of the atmofphere and earth, is the medi- um by which the moon aas upon the elements of the globe, is rendered probable by another fea. I poffefs the exaa dates of very few volcanic eruptions ; but by comparing fuch as I have, with the moon's place in her orbit, I find thefe eruptions begin or fuffer violent exacerbations, at the time the moon is in her pe- rigee or apogee ; or in her conjunaion or oppofition. The great eruption of Vefuvius in 1779 was augmented on the 8th and 9th of Auguft, when the moon was in her perigee. The tremendous eruption of Heckla in 1783, began on the firft of June, when the moon was in her apogee, and increafed till the 8th, after which it continued to be violent for a long time. An eruption of Vefuvius on the 10th of May 1784 was du- ring the moon's perigee An eruption of fire near Palermo in Sicily on the 13th of March 1785 was two days after her perigee. An eruption of Etna on the 19th of May 1780, the dark day in America, was the day after the full moon. A dark day on the 9th of Auguft 1732 was about the time of the new moon, and her apogee. The dark day at Detroit Oao- ber 16, 1762 was the day after her perigee, and one day be- fore the change. 292 The eruption of Vefuvius March 8th, 1730 was on the day after the new moon,and a great exacerbation happened on the 14th, the day before her apogee. The great eruption of the fame volcano in 1794 was announ- ced on the night of the 12th of June, nine hours before the full moon, by a violent earthquake. The eruption took place on the 15th. The darknefs in Canada, on the 15th and 16th of Oaober 1785 was on the days next preceding the foil moon and her peri- gee. The obfcurity on the 9th of that month was near the quadrature. The eruption of Heckla in 1766 began on the 15th of April, the day before the moon's apogee. The great eruption of Vefuvius and the earthquake, which bu- ried Herculaneum, on the 1 ft of November A. D. 79, were the fecond day after her perigee. The influence of the moon in producing ftorms of rain, fnow and wind, is univerfally admitted ; and that thefe happen near the pofitions of the moon already defcribed, no man will under- take to deny. The Weft-Indians expea hurricanes only near the time of the full and new moon ; or her perigee and apogee. This is further evidence that the efearical fluid is the inftrument of thefe commotions in the atmofphere. Elearicky is .known to be the caufe of winds, and its agency is vifible in producing hurricanes ; for experienced feamen foretel a hurricane by die unufual tranfparency of the water. Now it is a well known faa that elearicky poffeffes the lingular property of giving trans- parency to opaque bodies. A little before a hurricane in the Weft-Indies, feamen can fee the lead, at an unufual depth ; the fea alfo fwells and rolls upon the fhore in a lingular manner, tho the air is perfealy tran- quil. An effervefcence alfo or bubbling is obferved in the wa- ter. Dark clouds are formed, and the atmofphere, before the tempeft, is obferved by vapors fenfibly mephitic. See a letter from Gov. Ellis, dated March 6, 1789, in the 9th vol. of Mufeum, 215. Hence we obferve the correanefs of the com- mon faying among feamen, that " hurricanes come out of the 293 fea." They are evidently generated by extraordinary difchar> ges of elearicky. Hence they are moft frequent in the wind? ward iflands, which are all volcanic ; fome of them ftill difchar- ging fire and fmoke at times, and all of them evidently retting on a volcanic bafe. Further, that elearicky is the great agent in thefe agitations of the elements is rendered probable by the coincidences in time, between the more violent hurricanes, and great volcanic dif- charges from Etna, Vefuvius and Iceland. Witnefs the terrible hurricanes of 1747, 1766, 1772, 1780, 1784 and 5, all of which happened near the time of great eruptions from the volca- noes mentioned ; all of which are diftinguiflied in the annals of the Antilles, and ftill recolfeaed with horror by the inhabitants. -And this circumftance is no inconfiderable evidence, that the agent in volcanic eruptions, as well as in hurricanes, is efearici- ty, and that this element is often diflurbed or ejeaed from the whole globe, nearly at the fame time. Moft of the great tempefts, in all latitudes, happen near the moon's perigee and apogee ; and in thefe pofitions, we obferve effential changes in the temperature of the atmofphere. I have taken fome pains to compare the changes in heat and cold, with thefe pofitions of the moon, with a view to learn, whether the effeas are uniform. On examining the ftate of the thermometer for two years, I find that, in almoft every inftance of the moon's perigee and apogee, efpecially in winter, there was a confidera- ble change of temperature. Ufually the weather grew colder, as the moon approached her perigee. But the effeas were not uniform ; fometimes the weather became more temperate, at the perigee. But one general remark will be found true ; that in re- gard to heat and cold, the moon's apogee and perigee produce, at different times, precifely the fame effeas. This remark ac- cords with what has before been obferved in regard to earth- quakes. It is a general remark that the weather becomes cooler as the moon approaches the change. Should this remark prove to be well founded, the refuk would be this principle, that the cold is increafed, or rather the heat leffened, by the combined influence 494 of the fun and moon. This principle would accord with another obfervation juft made, that the weather is cooler, during the moon's perigee, which is generally true in winter. That is, the greater power is exerted by diftant orbs on our atmofphere, the more the heat is diminifhed. But this obfervation is not univer* felly true. It is true that our winter occurs during the earth's perihelion ; but this is ufually explained on the principle of the obliquity of the fun's rays—a folution that perhaps is not com- pletely fatkfaaory, altho, to a certain degree, it is doubtlefa juft. It is a popular opinion that vegetation is lefs rapid, and the flefh of animals lefs firm and fubftantial, and new-fliooting plants lefs vigorous, during the wane of the moon, than during her in- crement. This opinion is too general and too refpeaable, to be confidered the fruit of ignorance and credulity. Ariftotle alleges that the clofe of the lunar month is cooler than the other parts of it ; and that during the decreafe of the moon, the bodies of living animals poffefs lefs heat Chan at other times. De gener. animal, lib. 2. 4. Thefe remarks, whether true or not, coincide with the modern popular opinion juft re- cited. We are apt to negfea the opinions and praaices of barbarous nations, and to hold in contempt the knowlege of ancient na- tions. This often happens, I fofpea, becaufe we are lefs wife, than thofe whom we affea to defpife. Cefar in his firft book of the Gallic war, chapter 40, relates, that the ancient Germans, who were great obfervers of the phafes of the moon, declined engaging in battle, during the wane of that planet. He had of- fered battle to Arioviftus, but this commander declined a general aaion, and permitted only fkkmifhes. Cefar enquired of his priforters the reafon of this condua, and was told that k was cuftomary with the Germans to confult their venerable matrons, who, by means of lots and divination, pronounced on the pro- priety of giving battle ; and thefe had declared that it was not poflible for the Germans to conquer, if they engaged in aaion before the new moon. '* Non effe fas Germarros fuperare, ft ante novam lunam prselio contendiflent." See Cefar's Com- 295 mentaries, in the pafTage cited, and Henry's Hiftory of Bri- tain, vol. r. ch. 4. We have this cuftom of the Germans prefented to us, dif- guifed with foperftition ; but I ftrongly fufpea it had its origin in the obfervation of the fea, mentioned by Ariftotle, that in the decreafe of the moon, animal bodies have lefs heat and vigor. I am the more inclined to believe this, becaufe the doarin ac- cords with modern obfervations concerning the invafion of fevers, and efpecially of epidemic difeafes. Many medical authors concur in the fea, that difeafes more generally attack the human body on the fecond or third day before the new or full moon. On examining the accounts of feveral writers, I find the times of invafion to be two or three days before or after the new and full moon, or about the time of its conjunaion with the fun;. See Jackfon, Grainger, Lind and many other authors. Diemerbroeck is explicit on this point. He relates that in the plague of 1636, " two or three days before and after the new and full moon, the difeafe was more violent ; more perfons were feized at thofe times, than at others ; and thofe who were then feized, almoft all died, in a very fhort time. Many patients who appeared before to be flightly affeaed, nefclo qua vlrlum labefac- tione oppreffi, fays the author, by an unaccountable decline of ftrength, funk and died in a few hours." De pefte, page 9. From the obfervations of phyficians it then appears, that this debility of the animal powers takes place near the time of the con- junaion and oppofition of the fun and moon ; near the moon's perigee and apogee ; and in the fame pofitions in which earth- quakes and ftorms more generally occur. Of the reality of this effea ef the elements on the body, there can be no rational doubts. About the time of the change of the atmofphere, which indicates an approaching rain or ftorm, per- fons of debilitated habits of body, perceive the change, by a lofs of vivacity, dulnefs or heavinefs ; parts of the body that have loft their natural energy by means of wounds and tumors expe- rience painful or uneafy fenfations, by which ftorms are often pre- diaed. 296 Fowls perceive this change in the atmofphere, and manifeft their fenfations. Candles fparkle and fnap ; the tallow melt9 more freely, and the flame is lefs fteady. Thefe things were ob- ferved by. Ariftotle and Pliny. This change in the atmofphere is not only perceptible by the fenfe of feeling, but becomes vifible. Diftant objeas feen over water, and fome writers fay, over land alfo, loom, that is, rife, or appear elevated, feveral degrees, above their ufual altitude. The ear alfo will aid us in foretelling rain and wind; for founds become audible at an unufual diftance. Perfons in full health are not fenfible of thefe changes in the elements; at leaft, they are not fo much affeaed, as to obferve them. But from many years obfervation, I am convinced, that the catarrhal affeaions, which pafs under the popular name of colds, are occafioned by the alterations in the atmofphere which precede changes of weather, and few of them from the applica- tion of cold. I know this to be the cafe with myfelf ; thofe phafes of the moon, which have been mentioned as producing great effeas on the earth and atmofphere, rarely pafs, without affeaing me with flight catarrh. This has been remarkably the cafe, fince the fever of 1798, which left me in a ftate of debility, But many perfons can atteft the truth of the principle ; nothing being more common than for perfons to remark, that they can- not tell how they took cold ; and it being well known that ca- tarrhs are more general and fevere, on the tranfitions from cold to heat, than from heat to cold. The obftruaion of the glands is evidently the effea of an infenfible change in the atmofphere, probably by means of the decompofition of the elearicky and the vapor or other elementary fubftances of the atmofphere. And the winds to which we afcribe the changes of weather are un- queftionably an effea, rather than a caufe of thofe changes. Thefe alterations in the atmofphere appear to have fome con- neaion with the tides ; or rather with the caufe of tides. It is faid by feamen and other obfcrvers of the feafons, that full tides are apt to produce rain ; that rain which begins at high water will ceafe, with the recefs of the tide ; but rain beginning at low water, will be of confiderable duration. Thefe and other ©bfer- 297 vations, if jtift, manifeft an influence of the tides over the ftate of the atmofphere, or a dependence of both on one common caufe—the fame invifible energy of efearicity producing both effeas. It is a known fea that the flowing tide often brings with it a breeze of wind. This is afcribed to the friaion of the water on the air, and the caufe afligned may be fufficient to account for the phenomenon. But it may be fuggefted whether the efearicity of the atmofphere, may not produce both the tide and the wind. The intumefcence of the ocean, previous to earthquakes and hurricanes, which are evidently occafioned by efearicity, feems to bear a great analogy to the tides and to authorize my fufpicions. The fwell of the ocean during earthquakes, has ufually been af- cribed to the raiting of the land beneath it; but this cannot be the caufe, for fuch a fwelling of the land never takes place over whole continents. The fwell of the water is probably the effea of the elaftic powers of the efearicity difcharged, operating on the water itfelf. There are many diurnal and periodical phenomena, which are evidently conneaed with the lunar and folar influence, and de- ferve to be mentioned in this place. It is a well afcertained fea, that in the tropics, where the weight of the atmofphere is fobjea to very fmall variations, the barometer uniformly rifes and falls with the tides, about two thirds of a line. Encyclop. art. wind. This is a fmall varia- tion. But, It is alfo afferted that, in thofe regions, " the variations in the gravity of the atmofphere feem to depend on the heat of the fun, as the barometer conftantly finks near half an inch every day, and rifes again to its former ftation in the night." Ency- clop. art. atmofphere, [I fufpea the words " half an inch" to be an error.] Now, if the barometer depends, for its fluauations, on heat, we fliould fuppofe the fame caufe would operate in northern lat- itudes, and occafion a diurnal rife and fall, in an exaa ratio to h.eat and cold. In this cafe, a barometer would be a therruom- Vol. IL Q o 298 eter reverfed; rifing with augmented cold and finking with an increafe of heat. But this is not the fea. The barometer often rifes with the increafe of heat, between fun-rife and twelve o'clock. Heat therefore cannot be the direa caufe of the di- urnal depreflion of the barometer in the equatorial climates; un- fefs it has different laws, in different latitudes, which philofophy will not admit. Let us compare the feas ftated with the known phenomenon of the different forces of water, during the day and the night. The water-wheel of any mill, the altitude of the water and the refif- tance being precifely the fame, makes more revolutions, in a min, ute, during the night, than in the day time. I have long been acquainted with the fea, and it is known to every miller ; but as I have never feen a ftatement of it in any philofophical work, I have had the curiofity to make an accurate experiment to afcer- tain the difference. This was done on the night after the-2 8th of May 1799 ; the weather being perfealy ferene, the air free from vapor, not a breath of wind ftirring to ruffle the water, and the barometer, on the evening preceding, at half paft eight, Handing at 30 and one tenth. The firft obfervation was made at a quarter before 7 P. M. fometime before fun fet, the thermometer ftanding at 65 deg. when the wheel of the mill made exaaly 16 revolutions in a minute. The altitude of the water was marked with precifion ; but the delivery of the water not having been exaaly adjufted to the current entering the pond, the water rofe, and at 9 o'clock had half an inch of altitude beyond the mark. By this means, my obfervation at that hour was loft. By raiting another gate, the water was reduced to its former altitude, and by twelve o'clock the difcharge of the water was exaaly equal to the cur- rent, and from that time to fonrife, the altitude continued the fame. At twelve o'clock and from that hour to three, the wheel made 11\ revolutions in a minute ; the obfervations being often repeated, without a fenfible variation of refolts* Soon after three o'clock, a fmall acceleration was perceptible, but it did not amount to half a revolution, until about half paft three, when 299 the wheel made 18 revolutions in a minute, which accelerated movement continued till half paft four, when, being near fun rife, the obfervations were difcontinued. During the laft obfervations, I perceived a very fmall retardation of movement, but it did not amount to half a revolution. To prevent any difference of re- fiftencein the mill, not the flighteft alteration was made in the elevation of the ftone, or the quantity of wheat delivered from the hopper, from the beginning to the end of the obfervations. I had not a barometer with me at the mill, but about eight o'clock, on the following day, the barometer flood about one twentieth of an inch higher, than on the preceding evening. The thermometer fell, during the night, to 54 deg. From this experiment, it is obvious that the weight of the at- mofphere could not be the fole caufe of the acceleration of the wheel. The acceleration at twelve o'clock was almoft an elev- enth—at a later hour, a ninth of the whole movement. The in- creafed gravity of the atmofphere will not account for a tenth of the difference. We muft then refort to other principles for a folution of the phenomenon. It is commonly fuppofed that water is a non- compreflible fobftance ; but this opinion has been juftly queftion- ed. However this may be, I have little hefitation in refolving the phenomenon of the water-wheel into its increafed elafticity during the night. How or why the fubduaion of light and heat fhould produce or increafe this property in water, I leave for elearicians to determin. The effea cannot be afcribed to the increafed gravity of water, during the night, for no fuch increafe is obferved. It is an obfervation of feamen that fhips make more way in the water, by night than by day, with the fame force of wind. I fhould fufpea that the moifture on the fails might, in a de- gree, contribute to this effea ; but it muft be recolfeaed that in rainy days there is no difference in the moifture of the air by night and by day. Can the effea then be afcribed to the caufe that accelerates the movement of water-wheels by night—an in. ereafed elafticity ? If the gravity and denfity of water were augmented during the night, thefe would render the water more 3<*> buoyant, but retard the motion of a fliip, by increafing the tt- 'fiftance. We are therefore driven to the fame hypothefis, an increafe of elafticity, which renders water more buoyant when sft reft, and more impreffive when in motion, without an augmented denfity and weight. But I am not fore that the moifture of the air will not account for the whole effea. If the elaftic power of water is increafed by the abftraaion of heat, does it not follow that this power muft be greater as we recede from the equator ; and of courfe, any given force applied to the water in different latitudes, will occafion a vibration of that fluid, proportioned to its elafticity. Hence the fmall tides within the tropics, where the heat is nearly uniform ; and the •high tides in the northern regions, where the vibrations in the temperature of the atmofphere, are more confiderable. Yet 'faas do not permit us to afcribe this elafticity to cold. It is more probably owing to the quantity of efearicity, or to its pe- culiar combination v/ith aerial fubftances, of which cold is the effea. Perhaps the following obfervations will throw fome light on this fubjea. Ariftotle and after him, Pliny afferted that no animal dies, except during the ebb tide. " Nullum animal nifi aftu recedente expirare. Obfervatum id multum in Gallico O- eeano, et duntaxat in homine compertum." Pliny, Nat. Hift. lib. 2.98. " No animal dies, except during the recefs of the tide. This is particularly obferved on the coaft of Gaul ; and is at leaft true with refpea to man." The firft part of this obfervation is probably too general ; but modern feas confirm the aflertion, within certain limitations. A late minifter at Ban ie in Scotland, contiguous to the German fea, made a fimilar remark, after fifty years obfervation. Sinclair, vol. 4. 240. The reafon why Pliny has fpecified the coaft of France, as remarkable for the fea ftated, is very obvious. France lies on the main ocean, and the time of high and low water is the true • time. On the coaft of Italy, where there are no tides, the ob- fervation could not be made; and if made by the time of ebb tide in rivers and bays, it would not be juft. Another remark made by phyficians, is, that ceteris parlbust 3oi fnore perfons die during the latter part of the night, than at any othei time in the folar day. This remark has not come to me from sfufficient number of obfervations to command full belief; but it accords with a few obfervations of my own. If univer- fally true, it would contradia in part the remark of Ariftotle and Pliny ; but it is poffible, both remarks may be true with certain limitations. The fea may be more obvious, when ebb tide hap- pens between midnight and fonrife ; and lefs fo, when flood tide happens at that period ; that is, under the combined or feparate operation of the two caufes. Other feas lend their aid to fupport the obfervation that fome effential change in the properties of the atmofphere takes place, in the latter part of the night. This is the time when all fevers remit or intermit. The exacerbations and paroxifms of fever in- vade the patient, during fome part of the day, and fubfide in the latter part of the following night. Again. The chills that precede feveis ufually come on in the fame part of the day, that is, between midnight and fonrife. This is remarkably the cafe with epidemic difeafes, as all phyfi- cians agree. The fea has been afcribed to the debility induced by fleep ; but I fufpea it is owing to the debility induced by the fame change in the ftimulant powers of the atmofphere, which occafions the other phenomena before mentioned. It is obfervable alfo that fleep, in the latter part of the night, is more found, than at other times; an effea perhaps of the fame caufe. Lind obferves that in the Eaft-Indies, patients generally expire at low water—the fame fea is obfervable at the full moon—and convalefcents ufually relapfe at thefe periods. See his Treatife on the difeafes of hot climates, p. 86. From experience I can teftify that relapfes ufually occur, at thofe periods of the lunar month, when changes of weather take place. Ulloa was careful to note the time of the tide when earthquakes occurred in South-America, and he found them invariably to happen at half ebb or half flood—never at high or low water. Voyage, vol. %. B. 7. Ch. 7. 302 1 here are other periodical changes in the atmofphere which deferve notice. Great ftorms of wind, fpow and rain, ufually beffln, abate and ceafe at certain hours, viz. at fix, nine, twelve and three o'clock ; efpecially at fix and twelve. To this re- mark there are very few exceptions. Experienced accoucheurs inform me that in lingering cafes of child-bed illnefs, paroxifm6 of pains recur at the fame hours. What is ftill more extraordinary, we are affured by unqueftfon- able authority, that in volcanic eruptions, the difcharges are more violent at thefe hours, tiian during the reft of the day. Sir Wil- liam Hamilton, in his excellent account of the great eruption of Vefuvius, in June 1794, has the following pafTage. " The fe- ver of the mountain, as had been remarked in former eruptions* fhowed itfelf to be, in fome meafure, periodical, and was gen- erally moft violent, at the break of day, at noon and at mid- night." Univ. Magazine for Auguft, 1795. Thefe are the hours when we obferve great changes in the at- mofphere, and fudden effeason the human body in difeafes. The break of day is precifely the time when the water-wheel is moft accelerated—when fevers remit or intermit, and when the pa- tient, lingering under difeafe, fuddenly yields, and finks into his grave. To what caufe fhall thefe effeas be afcribed ? Not to lunar or folar attraaion, in the ufual fenfe of the word. Attraaion is confidered as a fteady principle operating uniformly under the fame circumftances ; and therefore the attraaion of the moon, whofe pofition in regard to the earth is every day changed, can- not account for periodical phenomena, at certain hours in the day. The influence of the fun will better folve the phenomena ; but how can the fame principle, attraaion, operating by uniform laws, produce the fame effeas at two oppofite hours, for inftance at noon and at midnight, which certainly is the cafe in regard to the exacerbations of volcanic eruptions, as well as in regard to the commencement, abatement, and termination of ftorms ? I do not know that any principle yet difcovered will folve the difficulty. But the phenomena bear a greater analogy to the op- erations of efearicity, than to any other principle in nature hith- 3°3 erto difcovered. It feems neceffary to invke to our aid repuMJon as well as attraaion, producing in oppofite points, the fame eft feas. The nature and operations of elearicky are Httle under- ftood, and probably will never be brought wholly within human comprehenfion. It is to be wifhed that experiments on the revolutions of water- wheels, in different latitudes, may be made, with care and pre- cifion, to afcertain whether any acceleration at night takes place within the tropics, and if fo, whether it equals the acceleration, in northern latitudes. And alfo whether the acceleration is great- er in the latitude of 60 deg. than in the latitude of 40 deg, Our millers fay that water has more force in winter, than in fum- mer. This may be eafily afcertained by experiment We are enveloped in a mafs of fluids, whofe combinations are in a continual procefs of change. The energy of aaion feems to depend on efearicity—or the principle of light, heat and fire; but lam perfuaded that the manner in which changes are produ- ced, is very little underftood. I will clofe this lengthy article by obferving that the phenomena of lunar and folar influence are fo well underftood and clearly proved, as to juftify in our minds, the great attention which the ancients paid to the influence of the planets on this globe. If they went into one extreme, by afcribing too much to that in- fluence, the moderns have erred, on the other extreme, by holding their doarins in contempt. The fun is the great fource of light, and his rays excite the heat which exifts in and around the globe. It moves this uni- verfal principle, which conftkutes the energy of the material fyftem, under the control of infinite intelligence. The moon is placed in the vicinity of the earth, to give vari- ety to the feafons, and by aaing on the elementary principle of heat, the occafions the viciffitudes of rain, fnow, fair, calm and tempeftuous weather. The changes which precede and produce thefe viciffitudes appear to be variations in the combinations of heat or efearicity, with the other elemental principles of the at- mofphere. Thefe modifications of the atmofphere, without any accefs of new matter or diminution of its mafs, produce differ. 3°4 ences in its denfity and elafticity, with all their various effeas on the animal and vegetable fyftems. Hence a mere modifica- tion or new combination of efearicity, with vapor or other ae- rial fubftance, may increafe or diminifh its ftimulus—-during the day, it may excite fever in the human body ; during the night, a fubduaion of excitement in the atmofphere, may induce de- bility, and favor the invafion of difeafe and the approach of death. Thefe are mere hints and conjeaures, intended to excite invefti- gation. With refpea to the fuppofed influence of comets on the ele- ments of this globe, I would remark, that on the principles here fuggefted, that influence is very clearly proved and may be eafily underftood. The feas ftated demonftrate that the fun and moon exert great powers on the globe; and the fea that earthquakes moftly happen in certain pofitions of the moon, prove that the medium of her influence is the efearic principle. Now comets are known to be of various magnitudes. Some of them are as large as Venus ; much larger than the moon ; with highly efearified atmofpheres ; and fometimes approaching near to the earth. The comet of 1577 came within lefs than a.million of miles diftance. Thofe comets which pafs the fyftem at an immenfe diftance from the earth can have no great influence ; but others approach- ing near, produce tremendous effeas. Hence during their proximity to the earth, the number and violence of earthquakes and volcanic difcharges ; tempefts, foundations from rains and extraordinary tides ; and moft fenfible changes in the powers of animal and vegetable life. That fuch are the effeas, is proved not only by the concurring opinions of all the ancient philofophers, who were accurate obfervers of nature, but by one unifoi m fe- ries of hiftorical evidence, for more than two thoufand years. On the principles of elearicky, which is difturbed, attraaed, repelled and modified in its combinations with other fubftances, by, the approach of diftant bodies, the folution of the phenomena is eafy and philofophical. 3°5 Of Elearicity. SOME modern philofophers fuppofe that the earth contain! yaft quantities of fire, which is the fource of the principal part pf the heat on the earth, the caufe of vegetation, of earthquake? and volcanic eruptions, and of hot fprings. See BufFun, and Darwin's Botanic Garden. Additional Notes, p. 145. New-York edition. . There are fome reafons to believe that particular parts of the earth abound with fire, or maffes of burning lava. This opinion is fupported by the ifluing of fmoke from the craters of certain volcanoes, for years in fucceflion, without any eruption of fire. But the theory which afcribes earthquakes to fteam or vapor, appears to be very unfatisfeaory. How can fteam be colkaed within die bowels of the earth, fufficient to fhake a continent of 3000 leagues in extent ? If a great quantity of water fhould by accident fall on a mafs of burning lava, the effea would not be a general equable fhake or concuffion, over a whole quarter of the globe, which fometimes happens in earthquakes ; but a violent fhake at the place of contaa, and a difrupture of the earth, by which the force of the fteam would be fuddenly difcharged into the atmofphere. This however is not the fea. Almoft all earthquakes in North-America are progreflive ; beginning in the interior of the country and proceeding towards the ocean, in a direaion perpendicular to the line of fhore, that is, from north- weft to fouth-eaft. Perhaps we can find a fatisfeaory folution of this phenomenon, upon ekarical principles ; but no caufe can be found in the known properties and effeas of fteam. One of the arguments ufed to maintain the theory of fteam, is derived from the known fea that fprings and ftreams are ufual- ly exhaufted by extreme drouth, fome time antecedent to earth- quakes and volcanic eruptions. But the fea, inftead of fop- porting the theory, operates to deftroy it. The hypothefis fuppofes that, at certain times, the fprings in the vicinity of burning lava defcend and fall upon it ; and the Vol. II. Pf 306 water being raifed into fteam and extremely rarefied, expels the burning materials in volcanoes with great violence ; and in earth- quakes, the force of the fteam alone afcends and fhakes the earth. But why fhould the water of the fprings find paffages to the lava, at fome times and not at others ? If the paffages were al- ways open, the water would always defcend. If they are open at particular times only, there muft be fome fubterraneous force exerted to open them, before the water comes in contaa with the fire ; the effea then or difrupture, muft take place, in a certain degree, before the fuppofed caufe can operate. Confe- quently the force exifts anterior to the difrupture which brings the water in contaa with the fire. This conclufion fuperfedes the ufe of vapor, But by what magic does it happen that all the fprings and rivers in the neighborhood of a volcano for inftance, difappear about the fame time ? By what mutual confent, can this-remarfc- able phenomenon be produced ? And why, after the eruption, do all the fprings and rivers refume their former channels ? Is it poflible to fuppofe thoufands of paffages, feattered over many leagues of earth, to be all opened at once, to convey fubterra- nean fprings to a particular place, a few months anterior to an eruption of fire ; and after the eruption, to be all clofed af once and the water compelled to run in its former channels ? Yet all this muft be admitted on the theory of fteam. That large volumes of water are fometimes thrown into the bafons of volcanic mountains and ejeaed, is true ; but, in fuch cafes, the difrupture is occafioned by a previous earthquake or force of fire, and the water is difcharged in mafs ; not in the form of vapor. It is a fea authorized by all hiftory and obfervation, that great earthquakes and volcanic eruptions are often, if not ufoal- ly, preceded by fevere and univerfal drouth. This drouth of- ten extends over whole continents ; and I find that the defeas of water which occafion the terrible famins in Egypt, India and China, of which we have many accounts, happen generally, (and L.fufpeaalways,) a few months before and during fome 3^7 great difcharges from volcanic mountains. I "have certain evi- dence that this failure of rains and fprings fometimes occurs ten months before the eruption. This was the feci in Bengal in 1769—and in America in 1762 and 1782. At other times, the drouth happens during the eruption, and in fome cafes, it is continued for two or three years, in which eruptions take place in different parts of the world. The drouth, on fuch occafions, is not occafioned folely by a failure of rain, but by the concurring influence of exceflive evap- oration. This fea is capable of demonftration. Sir William Hamilton, Univ. Mag, Aug. 1795, in his account of the erup- tion of Vefuvius in 1794, informs us that fome days previous to the difcharge, the great fountain at Torre del Greco began to decreafe, fo that the corn-mill worked by it moved flcwly. In the wells of the town, the water fell and it was neceffary to lengthen the ropes daily, Some wells became quite dry. In a vineyard, near the town, fome perfons were alarmed, eight days before the eruption, by a fudden puff of fmoke and explofion from the earth. It is recorded that Pherycides foretold an earthquake in Greece, from a fudden failure of water in a well. Thefe feas indicate unufual evaporation. It is obfervable alfo that the exhauftion of water extends, in fuch cafes, to a greater depth than ufual. The earth, below the ufual influence of the fun's heat and of rains, lofes its natu- ral moifture. Such probably was the cafe in 1782, when the cedar fwamps in New-Jerfey took fire and burnt to the depth of many feet. And this is probably what Livy meant, when, in foeaking of the terrible drouth in Rome, before the great erup- tion of Etna, B. C. 426, heufes the words" ingenito humore egens"—a failure of native moifture. In the vicinity of volcanoes, this evaporation may be accoun- ted for on the principle of fubterranean heat, which is fenfibly in- creafed, fome time before an eruption. But this folution cannot apply to countries a thoufand leagues diftant,>vhich fuffer extreme evaporation, at the fame time. There appears to be no way to account "for the phenomenon 3oo 4aut by the great principle of aaion, ekaricity. L.dccd thd difcovery of the fea, that moft earthquakes happen under par-- ticular phafes of the moon, and that volcanic eruptions are obvi-< oufly affeaed by her pofition in her orbit, feems to place this point beyond queftion. It feems then to be very certain that the ekaricity which ex- ifts in and about the earth is effentially influenced by the fun, moon and planets, but efpecially by the larger comets ; which pafs near the earth. The influence of thefe bodies, or the effen- tial laws of the univerfe, difturb this fluid and vary its diftribu-' tlons and its combinations with other fubftances. Previous to earthquakes, volcanic difcharges and hurricanes, it is evident from many phenomena already enumerated, the elec- tricity of the earth paffes out of it in unufual quantities ; and as the air is often a bad conduaor, the fluid attaches to it and car- ries along, the water upon the furface and within the bowels of the earth. This procefs continued for fome weeks and months, exhaufts all the rivers and fprings. The atmofphere, in the mean time, becomes more and more dry, and a worfe conduaor, un- til both air and earth become perfealy dearie, or non-conduc- tors. In this fituation, either a great demand for the fluid in fome diftant region, or a great accumulation of it in the bowels Of the earth, has prepared the Way for a fudden explofion, but no conduaing medium exifts, fufficient to convey it. A fall of rain, at this time, may create that medium ; and hence the com- mon faa that earthquakes happen foon after rain, fucceeding fe- vere drouth. If no rain falls, the fluid accumulates, till it for- ces a paffage through the great apertures, formed for the purpofe, the volcanic mountains, fetting fire, on its way, to the hydro- gene, and other inflammable fubftances, which the ocean gene- rates or depofits in their bofoms. I know not that thefe conclufions are juft, but the feas from " which I reafon, are indifputable. The uncommon difcharges of efearicity, previous to thefe great concuflions, are indicated not on- ly by the exhauftion of ftreams and fprings but by many phe- nomena in the atmofphere, fhowing it to be highly ekarifiedi Meteors, huge globes of fire, fhoot through the air, not only af • 3Q9 tt-r, but before the eruption. Witnefs the meteors of 1758^ 1762, and one in May 1783, mentioned in the preceding hiftoryj And Sir William Hamilton informs us that the air was unufual- Iy charged with ekaricity, fome days before the eruption of 1794.* Unufual halos and mock funs, fiery and luminous ap- pearances in the heavens, with extraordinary tempefts^ and hail, are evidences of the fame fea. •*' * ■ • The idea that the heat which we experience exifts in and about the globe, is undoubtedly well founded. The fun is prob- ably the great efearic of the fyftem, which excites into aaion the heat of the atmofphere and the earth ; but there is no reafon to believe that heat is principally derived from that body. The folar rays conftitute a very fmall part of the heat of the earth 3 but they excite it by the rapidity of their motions, or by decom- pofing that which exifts in the air and earth. Hence there appears to be little foundation for the opinion, that the inferior planets which are neareft to the fun, have mote heat, than Saturn and Jupiter. If heat is diminifhed in the ratio of the fquares of the diftances from the fun, it is on the principle that heat confifts in folar rays ; but this is a very quef- tionable doarin. Light is a fubftance, but does not neceffarrly contain heat; at leaft not any that is perceptible. It is probable, that if the folar rays falling on Saturn are di- minifhed in number, according to the doarin of diverging lines, that this defea is fupplied by an increafe of denfity or fofcepti- bility of excitement, in the atmofphere of that planet. The denfity and capacity of being excited may be in a direa propor- tion to the folid contents of the planet, or in a duplicate ratio to * May not the appearances of certain epidemic difeafes of inflam- matory diathefis be afcribed to this too highly electrified, and of courfe, ftimulant ftate of the atmofphere ? The influenza of 1708 was prece- ded by a meteor or fiery globe. In 1758 was a meteor and the meafles began in America. In 1771a meteor, and then commenced influenza and meafles. In 1775 a meteor, and the cynanche maligna prevailed.* In 1783 two meteors, and then commenced meafles and fcarlatina angi- nofa. In 1788 a meteor, and immediately began the m«afles. If thefe coincidences are all the work of chance, they are certainly a very An- gular kind of accidents. More facts and obfervations than I poflefs are aeceflary to fettle this queftion. * In America, and in Europe, influenza. 3to the diftance. Hence the larger planets are placed at the greater? diftaUce. And on this principle there is no ground to calculate, as Newton has done, the extreme heat which comets acquire in their perihelion. No fubftance of which we have any knowlege, Could fuftain the intenfity of heat which, he has calculated, the comet of i 680 muft have received. It is more confonant to the general arrangement of the univerfe, as far as our limited Under/landings can comprehend it, to fuppofe none of the great orbs that roll in infinite fpace, are either over heated or over cooled. Every orb has probably its own fund of heat, and the capacity of being excited, fuitcd to its place and deftination. The planets, the comets in the parts of their trajeaories moft f smote from the fun, and even the fun itfelf, may be inhabited.* * I take this opportunity, in difcufling the queftion concerning the origin of heat, to notice what philofophers have faid on the fubject of ttbe internal heat of the earth. Datwin, in his Botanic Garden, note 6, alleges the earth below the depth of about ten feet, to be always of the fame temperature, which is 48 deg. by Farenheit. He cites Dr. Franklin's obfervation, that fpring water at Philadelphia is of 5a de- gree*, which, he fuppofes, a proof of internal heat from central fires. For as the climate of North-America is colder, than that of England, he could not account for the excefs of heat in the water at Philadel- phia, beyond that of England, but by prefuming.it to be occafioned by internal fires. Yet in another pafTage, in note 7, the author intimates that he had an idea of a difference of heat in different latitudes, deri- ved from the aaion of the folar rays. Vet I cannot find any European author who appears to have had a correa idea of this fubjea; and Mr. JelTerfon, in his Notes on Virginia, query 5, has manifefted his ignorance of it, by a moft egregious miftake. Speaking of a cave in Frederick county, he informs, that the thermometer, which flood at $o deg. in the open air, rofe to 57 deg. in the cave. He then adds the following remark, " The uniform temperature of the cellars of the Obfervatory of Paris, which are 90 feet deep, and of all fubterranean cavities of any depth, where no chymical agents may be fuppofed to produce a factitious heat, has been found to be 10 deg. of Reaumer, equal to 54^ of Farenheit. The temperature of the cave above men- tioned fo nearly correfponds with this, that the difference may be af- cribed to a difference of inftrumcnts." It feems a little ftrange that fo grofs an error fliould have paffed un- torrecled, till this late age, on a point of fact fo eafy to be ascertained. The truth is, the temperature of the earth, below the diurnal and annual influence of the folar rays, which may be perhaps ten feet in folid earth and 30 feet in open wells, is regulated by the proximity of place to the equator, fubjea to fmall variations, from the pofition of the place in regard to the ocean and the height of the land. But what is remarkable, this temperature of the earth and water in the interior of the globe, is precifely the mean temperature of the climate, in the place where the obfervation is made. Thus, let the higheft and loweft points be taken daily by any good inftrument, and divide the 311 In a knowlege of mathematics and the application of math- ematical principles to the material fyftem, New.top is, and prob- ably will forever be unrivalled. But modern philofophers enjoy the benefit of many difcoveries made by experiments and by col- leaions of faas, which give them an eminent advantage over jh£ great aftronomers of the laft century. The ideas of Newton in regard to the tails of comets feem to have no juft foundatipn, and to be utterly repugnant to his own principles of the powers of fum of all the obfervations by the number of days in the year, the quotient will be the mean temperature of the climate, and precifely the temperature of the water, below the variations of heat and cold. If any difference fliould be found, it muft be owing to inaccuracy in the obfervations. It is more ufual to take three obfervations daily; at 2 o'clock P. M. the warmed time in the day, at fun-rife the coldeft time, and at fun-fct, which is found to be the mean temperature. By obfervations made in the city of New-York for one year, I found the mean temperature to be $s\; but this is i^ degree too high; owing to an excefs of heat -within the city, beyond the general temperature of the climate. The air in a city cools lefs at night, than in the country, and hence the morning obfervations were found to be too high. In many inftances, ice as thick as glafs was formed a mile from New-York, when an accurate thermometer in the city fell no lower than 40 deg. Hence the great error of determining the temperature of a climate, by obfer- vations made in a large city ; which is often done in Europe. The mean temperature of the climate in England, is 48 deg. That of Paris, 54^. This difference is owing to the infular fituation of England ; the atmofphere in the vicinity of large tracls of water being always more temperate, than on continents at £ diftance from the fea or great lakes. The following is the mean temperature of the climate of the re- fpective places, afcertained by obfervations. Fendon, north latitude, 51° 30 temperature, 480 Paris, 48 50 54-5 Quebec, 46 48 4* Rutland, (Vermont,) 4.1 34 434 Salem, (Maflachufttts,) 4a 30 47 Hartford, (Connecticut,) 41 44 49i New-York, 40 42 52 Philadelphia, 39 5° 5*i Virginia, (Frederick,) 39 nearly 57 Charlefton, (S. C.) 3* 44 66 Allowing a trifle for differences of inftruments, this table prefents to view the various mean temperatures of the climates mentioned. From this tjble naturally arife two obfervations. Firft the great dif- ference between the climate in Europe and America, m.der the fame parallels of latitude. Thus London in ji degrees north, has a mean temperature, almoft as mild as Hartford in 41. Paris in the 49th de- Tee has ;i climate, nearly as mild as the northern parts of Virginia in The 39th, and warmer than New-York and Philadelphia in the 40th. Again we obferve the great effect of the ocean upon the climate, Salem in Maflachufetts is upon the fea fhore, and Rutland, in Ver-1 mont, fifty or fixty leagues diftant; and one degree of latitude differ* ill gravity and refiftance. He fuppofed them to confitf of vapor 01 fmoke repelled from the nucleus by the force of the fun's heat. He feem to have been aware of the objeaion to this theory from the refiftance that muft be made to the alfent of the vapor, by the celeftial ether ; and therefore fuppofes an extreme rarefac- tion to take place, which removes that refiftance. But whatever rarefeaion may be fuppofed, ftill it will remain an incontrovertible principle in phyfics, that no fobftance that has gravity can be fupported,but in a medium which has more gravity' The vapor fuppofed in the prefent cafe could not be maintained in ftrait lines, without a medium of greater denfity to fupport it. Now, any medium capable of fupporting vapor muft furnifli great refiftance, and very much retard its velocity.* With thefe known principles in view, let any man calculate the velocity of vapor, driven from the nucleus of a comit, ne- ceffary to preferve a dkeaion nearly oppofite to the fun, in its perihelion paffage. Comets enter the folar fyftem in various direaions ; the planes of their orbits making various angles with that of the ecliptic. Their orbits are nearly elliptical, and the fun is in one of the foci of the ellipfis. By the univerfal law of planetary motion, according to which all revolving bodies defcribe equal areas in equal times, the mo- ence in the pofition of the places; yet the climate at Rutland is 3-§ degrees eolder than at Salem. On the other hand, Quebec, remote from the fea, tho on a river, with three degrees difference of northern latitude, has a difference of only i\ degree in climate. To afcertKin the mean temperature of any given place, it is only neceffary to plunge a good thermometer into water, taken from a depth, in which the temperature is uniform, at all feafons of the year. The mean temperature of water within the tropics is not exactly known, but it muft be very near 80 deg. by Farenheit. Water drawn from a depth of 20c feet in the Weft-Indies, is cooledby filtration in the air, above the earth in thofe hot regions. The difference in the temperature of Europe and America under the fame parallels, is nearly that of ten degrees of latitude. See Hutyoie's Regijler of the -w.ut/jer, Mem. Am. Acad. vol. 2. part I. Willi'urns'' Hijl. of Vermont. * I fubmit it to mathematicians whether on Newton's own principles, an atmofphere of denfity furHcieut to fupport a cannon ball, would noi; retard its'velocity, as^much as the prefent atmofphere does a feather put in motion, if fohis rarefaction does not in the leaft aid the afccnj (,i vapor from the body of a comet, 3'3 tion of comets muft be very rapid In their perihelion. The comet of 1770 was calculated to defcribe an arch of 50 degrees in 24 hours. This feems hardly credible ; but many comets defcribe an arch of 180 degrees, a femi-circle, in 30, 40, or 50 days. The perihelion diftanees alfo of the various comets are very different, and fo are the lengths of their tails ; fome of them extending a fmall diftance, and others to 60 and 80 millions of miles. Suppofe the perihelion diftance to be 30 millions of miles, and the length of the coma to be 70 millions. In this cafe the ex- tremity of the tail muft be 100 millions of miles from the fun. Now, either the vapor which is fuppofed to conftitute the tail, muft be fhot from the nucleus with fuch rapidity, as to reach the extreme point of the coma, in a few hours ; that is, it muft pats through 70 millions of miles, in a very fhort time, to pre- ferve a direaion nearly oppofite to the fun ; or the whole coma muft move forward with the nucleus. In the latter cafe, the extremity of the coma muft pafs along the periphery of a circle,* whofe radius is a line from that point to the fun, or 100 millions of miles,. Of courfe while the comet defcribes an arch equal to a femi-circle, the extremity of the coma muft pafs through the fpace of 150 millions of miles. I believe no kind of vapor of which we have any knowlege, could perform either of thefe journeys in the time given. On the other hand that gravitating fubftance would not have paffed thro the diftance fuppofed, from the creation of the world to this time. On fubjeas of this kind, we cannot arrive at certainty. AH we can do is, to reafon from analogy and from probable conjec- tures. We know of no fubftance in creation, capable of pro- ducing the phenomena of the comas of blazing ftars, except efearicity or light. No other fpecies of matter paffes with a rapidity that will folve the phenomenon of the length of the coma preferved in a direaion oppofite to the fun. The theories of Kepler and Hamilton are more rational, than that of New- * The figure would not be a circle, but it i*not material to the ar- gument. *■=.-".. Vol. II. QLq - 3l4 ton. The tails muft confift of efearicity repelled from the nu- cleus by the force of the fan ; or muft be merely the rays of light colored by their pafTage thro the comet's atmofphere. Thefe hypothefes may not folve all the phenomena ; but they will account for the principal ; and are repugnant to no philo- fophical principles, The curvature of the coma has been alleged as an objeaion to this hypothefis. But in fea this is a confirmatory argument in favor of it; for it is analagous to the curvatures formed by af- cending ftreams of ekaricity in the lumen boreale ; indeed it feems to be a law of efearicity to move in bending lines ; and for any thing we know, this phenomenon may refuk from the nature of that fpecies of matter, and be independent of refift- ance. In regard to the tranfparency of the tail, it refembles alfo the lumen boreale. Thro both of thefe luminous appearances, the ftars thine with undiminifhed luftre ; but vapor, however rare, would refraa their light, and in a certain degree, interrupt our vifion. An EtTay on Comets by Andrew Oliver, publithed 1772, af- cribes the tails of comets to air extremely dilated and repelled from the nucleus by the power of the fun ; but this hypothefis is liable to all the objeaions ftated againft the theory of Newton. My own opinion refpeaing the material fyftem, is this ; that ah atmofphere, the batis of which is ekaricity, fills infinite fpace and involves in its bofom all the folid orbs which thine in the ce- leftial regions. This may be denominated the mundane atmof- phere. My hypothefis refts on the following reafons. Firft. The large meteors or globes of fire are formed in re- gions far beyond the limit afligned to the earth's atmofphere. Their altitudes vary from 40 to 80 miles. At the height of 80 miles, then, there muft be the matter of an atmofphere, capa- ble, of generating globes of fire of half a mile in diameter ; and of communicating founds, as full and diftina, as the air near the "earth ; for the explofion of one of thofe globes refembles thunder. Secondly. The lumen boreale has been orte'u calculated to be vifibteat an elevation of 7 "or "Boo miles. I do not rety on 3*5 trie accuracy of thefe calculations, on account of the difficulties attending them. In fome inftances we are very certain that this light exifts in the regions of the higher clouds. Thirdly. The tails of comets muft be matter, or depend on matter for their coloring by which they become vifible. In ei- ther cafe we have evidences nearly amounting to demonftration that a material atmofphere fills the boundlefs regions of fpace. Fourthly. But an argument of ftill more weight in my mind, is one drawn from the neceflky of fuch an atmofphere, as the me- dium of attraaion and repulfion—the principles that connea an'd bind together the vaft orbs that roll in etherial regions. I can have no idea of fuch an immenfe power exerted in an immenfe void or vacuum. It feems probable that the parts of our atmofphere which con- ftitute weight, and are fuppofed to influence the barometer, are limited to the diftance of a few miles from the earth. Water, for inftance, is a fubftance deftined to anfwer certain purpofes on the globe, and is probably confined to its neighborhood. But the principle of efearicity may be, and undoubtedly is, a nongravitating and permanently elaftic fubftance. This may be, diffufed through infinite fpace, and by its amazing elafticity, may be capable of communicating motion or force from planet to plan- et, with the rapidity of light. Newton fuppofed infinite fpace to be filled with a fubtle fub- ftance which he called ether. Had this great man been acquainted with the laws of efearicity difcovered fince his days, he probably would have exchanged the term ether, for ekaricity. By means of this powerful principle, the planets all influence, each other ; and become the means of diverfifying each other's feafons ; fometimes by attraaing, fometimes by repelling, and fometimes difturbing the proportions of this fubftance, or influen- cing its mechanical laws, by which it is combined or decompo- fed with other atmofpheric fubftances* Hence we may account for the frequency of earthquakes* volcanic eruptions and violent tempefts, under particular phafej of the moon, and efpecially during the proximity of comet?. The ekarical matter accumulated in the earth by its own lays, or by reafon of an unufual demand ab extra may, during the ap« 316 proaeh of thefe orbs, be fuddenly called into aaion, and occa- fion extraordinary tumults in the atmofphere. Perhaps alfo we may, in this hypothefis, find a folution of the phenomenon, fo interefting to man, and fo myfterious, why the approach of comets never fails to be attended with epidemic dif- eafes. The fea, in regard to comets which come near the earth, is unqueftionable ; and it is equally certain that earth- quakes, volcanic eruptions, meteors and many other ekarical phenomena, are, at fuch times, more numerous and violent, than at other times. Now it is proved by experiments that the fibres of living ani- mals are the moft perfea conduaors of ekaricity, while the in- teguments which cover them are non-conduaors. A confequence of thefe principles muft be, that in all the motions or operations of ekaricity in the atmofphere, the nerves muft be the principal fubjeas of its influence. Hence if the atmofphere is, at times, elearified beyond the degree which is ufual, and neceffary to preferve the body in a due ftate of excitement, the nerves muft be too highly excited, and under a continued operation of undue ftimulus, become extremely irritable, and fubjea to debility. Shall we not find, in this hypothefis, a rational folution of the phenomenon which has puzzled medical men, the exceflive irri- tability of the nervous fyftem, in times of epidemic difeafes, which facilitates the invafion of fever ? Shall we not account for the eruptive difeafeswhich always precede peftilential epidem- ics, on the principle of the great debility of the extreme veffels, induced by the weaknefs of the nerves which fpread over the human body near the furface, by which means thefe veffels are rendered incapable of performing their ufual fecretions ? Shall we not be able to account for the remarkable coincidences in time between the influenza, and unufual ekarical phenomena, as volcanic eruptions and earthquakes ? May we not account for epidemic meafles, in thofe years when the atmofphere fhows ev- idences of high efearification ? And will not this principle ex- plain the difeafes among animals, the defea of vegetation, and the extraordinary generation of infeas, during peftilence ? It is well known that vegetation may be greatly accelerated by artifi- cial efearicity. Is this effea produced by what is called ex- 3*7 citement ? And if fo, how do we know that a fimilar power, operating on the elements, may not call into exiftence innumera- ble infeas ? To what other principle fhall we afcribe the unufual Jize of common infeas, when they precede and accompany pef- tilence, a fea well attefted ? There muft be a caufe for thefe phenomena, and where fhall we find it, but in the universal principle of excitement ? It is now agreed among philofophers that efearicity is the im- mediate agent in the formation of rain, fnow and hail. In con- firmation of this theory, my enquiries into the caufe of epidemic difeafes have led to a difcovery, that thofe years when volcanoes difcharge great quantities of fire and lava, including fome months before and after the difcharges, are by a great difference, moft produaive of hail. Hence the immenfe damage done by hail- dorms in thofe feafons which are exceflively dry and hot; thefe years being clofely attendant on volcanic eruptions. The theory which afcribes hail to extreme cold is defeaive. We know that pieces of ice of three, fix and even nine inches in circumference fometimes fall in hail-ftorms. By the laws of gravity, a hail- ftone muft begin to fall, as foon as it begins to be formed; and as it requires but a few feconds to defcend, it is eafy to conceive that mere cold cannot occafion a congelation rapid enough to form pieces of ice of half a pound weight. The procefs is elec- trical, and almoft inftantaneous ; and we know that real foow may be artificially and inftantly produced by means of condenfed air and ekaricity. Hence we are led to the caufes which con- nea fevere winters with volcanic eruptions ; we derive the ex- treme heat of fummers and cold of winters, which fo generally accompany peftilence, from the fame caufe, a fuperabundance of efearicity. Hence we are led alfo to the caufe of the apoplexies, lethar- gies and eruptive difeafes, which almoft uniformly follow great volcanic difcharges and earthquakes in Italy. The fyftem, and ef- pecially the nerves, are exceflively excited, and lofe their energy. It is on the fame principle alfo that we explain the phenomena of freezing," when the thermometer is above the ufual point of froft. This has been obferved near volcanic mountains, where the atmofphere is highly charged with efearicity. In 1730, 3** Dr. Cyrillas found by a thermometer made by Haukfoee, that water, near Vefuvius, froze with the mercury 10 degrees above the freezing point. Phil. Tranf. No. 474. Bad. Mem. vol. 9. 199. Trie nature of this element, ekaricity, is little underftood. It is the m»dern opinion that heat and light are only modifica- tions of the fame element. This is analogous to what we know of water, which exifts in the form of water, of vifible vapor and air. It is fuppofed that efearicity cannot be infulated in the human body. But if it cannot be infulated in the form of ekaricity, may it not in the form of heat, and thus be the direa caufe or matter of inflammation ? If it can be accumulated and infulated in this form, may not conduaors be formed to draw it off in the form of efearicity ? Mr. Vinal relates that he fpeedily re- moved local inflammation occafioned by a burn and fcald, by the application of a negatively charged ekarical machine. Mem. Amtr. Acad. vol. 2. 144. Should this doarin be well founded, the fuccefs of metallic points in removing topical inflammation, will be explained and eftablifhed. * The proofs of the altitude of the atmofphere from the power of refraaing light, are now known to be fallacious. No man will fuppofe the atmofphere to be lefs elevated, in the equatorial regions, than in the polar circles ; yet the duration of twilight, under the equator, being lefs than in places remote from it, proves that the power of refraaion will not determin the height of the atmofphere. The power of refraaion is in a ratio to the diminu- tion of heat, or increafe of cold, in the atmofphere ; or perhaps to the increafe of ekaricity. Nor will it be correa to fay that the power of refraaion de- pends on the denfity of the atmofphere, unlefs denfity can exift independent of gravity. The atmofphere in the polar and tem- perate regions raifes the barometer no higher, than under the equator ; nor is the mercury in barometers generally higher in winter, when the thermometer, by Farenheit's feale, is 10 de- grees under cypher, than in fummer when it is at 98 deg. the temperature of blood heat. 3*9 If denfity implies or involves in it gravity, then the atmofphere at the equator is as denfe as in any diftant latitude, for the bar- ometer is as high in one as in the other. But if the atmofphere is as denfe and as heavy, caeteris paribus, in one latitude, as in another, then the powers of refraaion, in different latitudes, which are various, cannot depend on denfity. It is indeed very queftionable whether denfity and gravity are the principles which wholly influence the barometer. The bar- ometer falls, as it is elevated above the furface of the earth; but the atmofphere retains all its powers of fuftaining refpiration and ckculation, at an altitude of 15,000 feet. What are the aerial phenomena that attend a fall of the bar- ometer ?_ How can the weight of the mafs of air furrounding the globe, be fuddenly taken off, over a whole continent ? What be- comes of its gravity, and the principle of attraaion on which it is fuppofed to depend ? Are they removed, expelled, or fuf- pended I I fufpea the theory which afligns to the barometer the province of determining the gravity of air, is fundamentally defeaive j and that inftead of variations in its weight, it indicates only va- riations in the combinations of its parts, which diverfify its elafti- city, and its operation on the barometer, as well as on the human body. When the atmofphere is full of vapor, the barometer ufually falls, and we feel a depreflion of fpirits. It can hardly be true, that the prefTure of the whole atmofphere is lets, at foch a time, than when the air is clear and the barometer high ; for this vapor circulates near the earth and the higher regions of the air are as clear and as ponderous as ufual. If the denfity of the air near the earth fhould be leffened, the confequence muft be the air from higher regions, which retains its gravity, muft inftantly ruth in to fupply the defea. The only way to account for the variations of the barometer, appears to be on the principle before mentioned. The ak appears to be lefs elaftic, when the heat is combined with vapor, and the mercury falls. It feems neceffary to take into view thefe confed- erations in order to folve the phenomena. The general prefTure of the atmofphere or gravity, is probably uniform, and it is 320 the various changes in its elaftic powers, which occafion'the vibrations in the barometer. Every dairy woman knows that thunder and lightning will al- moft inftantly coagulate milk ; that is, when efearicity is united with vapor, and paffes, in a vifible form, from cloud to cloud, or between the clouds and the earth, milk turns, or coagulates— fo it does, during a rainy day, in fummer, without thunder, with the thermometer at 64 deg. as I know by obfervation. This condition of the atmofphere, may be called its decompofed ftate. The barometer falls, vapor becomes vifible, the funaions of the body are languid, milk coagulates, objeas contraa mould, in fhort the atmofphere is unelaftic, and ill-fitted to maintain vigor in animal or vegetable bodies. Thus alfo the fermentation of beer is checked and deftroyed by thunder, and no human art has been found to reftore it. By what procefs of ekaricity is this fudden change effeaed ? I have remarked in the preceding pages, that a peftilential at- mofphere is not correaed or moved by the force of wind—no tem- peft expelling an epidemic fever from a city, unlefs at the clofe of the feafon, and accompanied with heavy rains. How can we folve this difficulty, but upon the hypothefis of an ekarical atmofphere which is ftationary ? Dr. Franklin proved that " an ekarified cork ball at the end of a filk thread, whirled never fo rapidly through the air, for a length of time, loft none of its ekaricity. He found alfo by an experiment that an ekarical atmofphere raifed round a thick wire, inferted in a phial of air, drives out none of the ak ; nor on withdrawing that atmofphere, would any air rufh in." On Ekaricity, Lond. ed. 97. It is alfo proved that a moft violent blaft of wind, thrown acrofs a ftream of ekarical matter, has not the leaft effea upon it. Thefe experiments prove that air furnifhes no fenfible refiftance to the motion of ekaricity, and that it exifts in air without ex- panding or comprefling it. In fhort it proves that ekaricity aas entirely by its own laws, and is not controlled by the agita- tions of the air. 32I Will not thefe obfervations throw light on the fea of a fta- tionary atmofphere in cafes of peftilential epidemics ? Is not efearicity the bafis of the common atmofphere, and immoveable by wind ? And does not a peftilential air confift partly in fome combinations of this element, with other aerial fubftances, which are not moved by wind ? This is fuggefted merely for con- fideration ; for it appears to me improbable. Froft deftroys the peftilential condition of the atmofphere, and this is fuppofed to aa upon the deleterious fubftances arifing from the earth, or hu- man body. Befides, a peftilential atmofphere rifes but a few feet above the earth, which indicates that its pernicious qualities are denfe and gravitating fubftances. Indeed two caufes feem to concur in the origin of peftilential fevers—an ekarical condition of the atmofphere which renders the nervous fyftem extremely irritable, and the body of courfe prone to fever ; and a colfeaion of morbid matters arifing from living* and dead animals, and putrefying vegetables. Wind may remove the latter caufe, if acceffible, which however is never the cafe in large cities; but cannot affea the influence of the former. Froft has accefs to all morbid caufes, and renders them inert. It alfo reduces the ftimulus aaing on the human body, and renders it lefs kritable. But the ekarical ftimulus remains. Hence altho the progrefs of the fever is arretted by cold, the type of it is vifible in the difeafes of the winter. The irritability of the fyftem, from ekarical caufes, ftill re- pains ; and gives to the fevers of winter the peculiar fymptoms of peftilential or typhus pleurify, and peripneumony. A remarkable property of efearicity is to give polarity to the needle of a compafs. A violent ftroke of ekaricity, deftroyed the virtue of the loadftone, and reverfed the ends of the needle of the compafs onboard of Capt. Waddell's fhip in 1751 ; and a fuitable difcharge of that element will give polarity, like the * I mention the morbid matters from living bodies, among the caufes of peftilence. 1 am perfuaded that perfpiration in cities furn.ihcs more poifon than ftreets and alleys. It fill* all clofe rooms, efpecially bed room,; in clofc-built ftreets, it infeas the very atmofphere; and a more virulent poifen does not exift, than perfpirabk matter in a con- denfed and fermenting ftate. This can only be deftroyed by a liberal ufe tf water. Vol. II. R « 3*2 magnet. Hence it is concluded that magnetifm depends on ekaricity, but in what manner, feems to be myfterious. It is well known that the needle is fubjea to variations, which are different in different parts of the earth ; and in fome degree, periodical. It has alfo a fmall diurnal variation ; receding from the eaft or influence of the fun from 8 o'clock in the morning to 2 in the afternoon ; and from the weft, or the fame influence, from 2 o'clock to 9 P. M. ; and during the night, remaining ftationary. Is not this owing to the repulfion of light and heat \ If fo, is there not an analogy between this diurnal variation, and the phenomenon of polarity ? If light and heat, falling on one fide of the needle, repel k in a fmall degree ; is rt not ra- tional to conclude that the equatorial heat, thould repel the mag- netic point, and direa it to the north ? That is, the needle points towards that portion of the atmofphere which is moft per- fcaiy efearic: It may be objeaed that the needle does not always dire& it- felf to the fame point. True ; but there is fome periodical revo- lution in the ekaricity of the terreftrial regions } as the appear- ance and difappearance of the lumen boreale, at certain periods, ■warrants this fuggeftion. It feems to be admitted that there is a current of ekaricity from the equatorial regions towards the polar regions, within the earth, and in the upper parts of the :atmofphere, a current of the fame element from the poles to- wards the equator. This idea is derived in part from the lumen boreale, and receives countenance from the fea, that a bar of iron, ftanding direaed towards the pole will acquire polarity or magnetic properties ; but direaed towards other points in the heavens, no. fuch effea is produced ; indicating a ftream of e- fearicity pairing through the bar, from the center of the earth towards the pole, but not in any other direaion. Should this idea be well founded, and fhould it be admitted that the lumen boreale is a current of ekaricity from the north to the fouth, will not the-periodical appearance and difppearance of this light, indicate a revolution in that current about the axis ©f the earth, or perhaps an axis of its own ? If fo, on what laws does it depend, and how will it agree with the variation* of the compafs-? •- S*3 It will be faid, that the variations are different in different places, and not uniform in the fame place. True ; but die gea* eral courfe of variations in the fame place is tolerably uniform. With refpeft to different degrees of variations in various pla- ces, I have one obfervation that is probably new. It is very probable, if not evident, that the diftributions or forces of elec- trichy are different in different quarters of the globe. I fay diftributions or forces ; for a difference in the ftate of exiftence or modes of aaing, will as well account for the phenomena, as ■difference in quantity. My reafons for this opinion are, that the barometer has different altitudes, in different places, at the fame time. The mean altitude for a month or a year, in places of the fame elevation, is very various. Hence we conclude that the weight of the atmofphere cannot be the caufe of thefe varia- tions, for this on a level of the ocean, muft, on hydroftatic prin- ciples, be every where the fame. Yet the aaual differences a- mount to one half or two thirds of an inch. See Phil. Tranf. No 435. Bad. Kern. Vol. io» 81. It is eafy to account for this difference of prefTure on the prin« ciple of different combinations of the dearie principle with vapor or other local matter in the atmofphere, which may vary the force or elafticity of the air ; but I do not fee how the weight of a fluid alone, whofe prefTure muft be equal, if of equal height and den- fity, can account for thefe differences. It is utterly repugnant to all known principles of the equable prefTure of a gravitating fluid, to fuppofe a mere change in the form or compofition of that fluid, fhould alter the abfolute weight. Water admits none of thefe varieties, being always of equal denfity and gravity at equal altitudes. On the fame principle of a difference of prefTure or elafticity in air and water, without a change of weight, perhaps we may account for the very different elevations of the tide in different places, and in fome inftances, in the fame latitude. It is rational to conclude that the ekaricity is various in its combinations or quantity, in different places, according to the heat of the climate, the neighborhood of land and high mountains, or perhaps to the feats of volcanoes ? The fea that tides do not rife as high, on the main ocean, as near land, feems to countenance this idea. 3*4 It feems jo indicate that the medium by which the moon iriflV ences the water, has different powers near the land and at a great diftance. Another faa that feems to favOr the hypothefis that ekaricity is the inftrument of tides, is, the great irregularity of tides. In many inftances there have been preternatural ebbirigs and Sowings of the tide—fometimes the river Thames, for inftance, has been left almoft dry, for many hours, when there has been neither wind nor earthquake to account for the phenomenon.* * A rccefs of this kind is mentioned in 1114, when the Thames for the whole day, on the 15th of October, was fo tow, that children wa- ded over between the Tower and London bridge. In 1247 there was a ceflation of the flowing of the tides for three months, before a fevere earthquake. See Short vol. 2. I45. I fhould not be inclined to credit thefe relations if modern obfervations did not ferve to confirm them. On the nth of March 1785 and 25th of January 1787, the Tiviat, a large river in the fouth of Scotland, receded and left its channel dry, in the former inftance, two hours, and in the l?.tter,/o«r. No convuilion of the earth was known in that neighborhood, nor within two or three weeks of the firft inftance. An earthquake happened on the 36th of January, the day after the fecond inftance, but could not be the caufe. A fimilar recefs happened on the day of the earthquake, in the river Clyde. On the 12th of September 1784, in perfectly calm weather, the water in the Lock Tay in Scotland fuddenly ebbed 300 feet and left the channel dry, then flowed again, and thus alternately rofe and fell for two hours. The fame phenomenon, in a lefs degree, occur- red in levcr'al fucceeding days. Sinclair, vol 6. 624. The fa^s related of the fea and rivers in Holland on the day, but not at the hour, of the earthquake, at Lifbon, in 1755, when fhips fnapped tHeir cables, and water dafhed over the fides of veffels, without the le.aft fenfible motion of the earth, are ftrong proofs of the fame infenfi- ble but immenfely powerful action of the electricity of the globe. The fwelling of the ocean in the time of earthquakes is not fo much owing to the rifingof the earth beneath, as to the force of electricity. The intumefcence fometimes begins before the fhock, as it does before hurri- canes in the Weft-Indies. In Scotland, during the great earthquakes in Calabria, irt 178a, the water in the locks was agitated without any motion of the earth, and the mercury in the barometer fell within the tenth of an inch of the bottom of the fcale. On the iathof February 1787, the barometer at Edinburgh fell nearly to the fame point. Thefe phenomena can be refolved into no caufe but fome operation ef electricity, and they add much weight to my fufpicions, that tides are governed by fome laws of ekaricity, which are influenced by the phafts of the moon. The great fall of the barometer in Scotland is a ftrong evidence that. the fame energetic principle governs that inftrument. It is abfurd tc* fuppofe the atmofphere could have loft fuch a portion of its weight. Indeed it is far from being impoffible that the rife and fall of the ba- rometer may be occafioned by the force of electricity aaing on the qichfilver itfelf. |f anyperfpa fliould hectare to believe thai a, mere change in the 3*5 Thefe irregularities have invariably happened in years, which have been remarkable for ekarical phenomena. To this point I have paid particular attention. They are not always attendant on earthquakes, or volcanic eruptions ; but they occur in the fame year, or near the fame period ; evidencing that when thofe vifi- ble difcharges take place, infenfible difcharges take place in re- mote countries, and on the oppofite fide of the globe. Should it be admitted that ekaricity may be unequally dis- tributed or operate with different forces, in various places, ac- cording to its combinations with aerial fubftances, at different times, we may find fome probable caufes of the great diverfity of difeafes in the fame year, as well as of the different heights of the barometer. The ftimulus applied to the human body, may be different in various places, according to the predominant ope- ration of one or more of the following caufes. I. Soil, which may affea the air in various ways. II. Situation in regard to elevation, to water, hills, moun- tains, minerals, frefh air. III. The population of places, and all the confequent evils of noxious exhalations. IV. The cultivation of a country, which has a moft falutary effea on the atmofphere. It is very certain that the condition of the atmofphere is very different, in places which appear to be equally favorable to combination of ele and the launching of the frigate in Baltimore, in the epidemic of the latter year. Vol. IT, 5 s ^3° The only effeaual fafety is in flight. When a few cafes of the plague firft appear, they fhould be removed, or other precaution's taken to prevent any ill effeas from infeaion. They may be fpo- radic cafes, and fuch precautions may fave a city from the further progrefs of the diftemper, among vifitors and attendants. But if thefe precautions prove fruitlefs, as they ufually will, and as they always will, when the difeafe is the effea of an atmofpheric principle, which is the fea, nineteen times in twenty, the only certain means of fecurity, are in quitting the city. The prac- tice of fhuttlng up, which is cuftomary in the eaft, if the people can live in high rooms, may fave life, but it is very inconvenient, and lefs fafe than an abandonment of the infeaed town. On Venefealon. THE extenfive .mortality occafioned by the plague, the ra- pidity of the difeafe, and the virulence of its poifon, which often defies all medical aid, have called forth all the exertions of talents and knowlege, to invent fome mode of defeating its ravages. It is agreed on all hands, that perfpiration, if induced on the firft feizure of the patient, is the moft effeaual prefcription. Hence the univerfal ufe of alexipharmks in peftilence. But it often happens, that no application whatever will excite perfpiration, and efpecially, in the later ftages of the difeafe. No part of the praake of medicin has excited fuch warm controverfies, as venefeaion. It is foreign from my plan to dif- cufs this queftion ; my remarks are intended rather to explain the caufe of this diverfity of opinions, from my obfervations on hiftorical faas. Moft of the medical writers who were perfonally acquainted with the true plague, in former ages, when it frequently over- spread Europe, have decided againft bleeding. In th'e plague which ravaged all Trance in 1565, Charles IX. then king, demanded of all the phyficians to give information of the beft mode of treatment, and they unanimoufly decided againft the praaice of bleeding liberally. Skenkius, p. 7 70. 33* Ambrofius Paraeu?, in the fame plague, made extenfive en« quky, as to the fuccefs of bleeding and purging, the anfwer pf his medical friends was, that in all cafes, thefe evacuations, if powerful, were fatal. Sennertus, p. 356. Foreftus, obferved, in the plague of 1557, at Delph, that thofe all died, who were bled after twelve hours from the inva- fion of the difeafe. Palmerius has teftified to the fame effea, and fo has J. Ant. Sarracenus, in defcribing a plague in Ge- neva. Fallopius remarked in the plague which raged from 1524 to 1530, that all died who were bled. This was obferved alfo by H. Florentus, a phyfician of Leyden—by Simonius, in the plague of 1602—Hildanus, in the plague at Laufanne, and a multitude of others. See them colkaed in Diemerbroeck, de pefte, 130. and fequel, who found in the plague at Nimeguen " venefeaion- em damnofiflimam fuiffe"—bleeding was extremely injurious. On the other hand, we have in the fame author a long lift of names of eminent phyficians, who warmly advocate venefeaioa. To this lift maybe added the name of the celebrated Sydenham. The fource of this difference of opinion is doubtkfs the dif- ference of the fymptoms in the difeafe under different conftitu- tions of air, in different places, apd in different habits. The great difference in the fame difeafe, under different epidemic con- ftkutions, was moft diftinaly obferved by Sydenham ; and this variety feems to conftitute no fmall nor eafy part of the phyficiaH's inveftigation. Sydenham obferved what is undoubtedly true, that the tame difeafe is charaaerized with different fymptoms, under different conditions of the air ; and often the fame apparent ftate of air produces very different difeafes. It is very evident, that the vi- fible qualities of the feafons are riot the only circumftances that modify difeafes. The learned Boyle remarks the great diverfity in plagues, requiring remedies altogether different. Vol. 5. p. 6q. Hence at one time, the plague, in a few hours after invafion, induces a ftate of debility, in which bleeding will, in almoft eve- ry cafe, accelerate death. At other times, the difeafe may main- 33* tain, for twa or three days, a highly inflammatory diathefis, iri which a timely, and judicious ufe of the lancet may prevent a fa- tal termination. I am perfuaded that hiftory will juftify thefe remarks, and make praaitioncrs very cautious of prefcribing for the name of a dif- eafe. This caution is more efpecially neceffary on the firft ap- pearance of an epidemic, before the ruling type of the difeafe is fully manifefted. The doarins of Sydenham, in regard to the controlling influence of different conftitutions of air, feem not to have been ftudied and purfued, with the diligence due to their importance. They are the bafis of an interefting branch of phi- lofophy as well as medicin ; being grounded on thofe varietiesin- cident to the fame objea, which charaaerize all the works of creation—varieties which conftitute the revolutions in the fame difeafe, analogous to thofe already defcribed in a feries of epi- demics and in many other phenomena of the world. On Vapor or Mephitic Air, extricated from the earth by means of difcharges of the ekarical fluid. I HAVE fuggefted in the preceding pages, that epidemic difeafes may be fometimes occafioned by a vapor extricated from the earth. That foch has been the fea in cafes of earthquakes, has been proved by feveral examples ; that a deleterious vapor may be expelled from the earth and produce difeafes, without a concuffion, appears from the cafe at Rouen in 1753, and the ficknefs and death of fifh are ftrong evidences of the truth of the principle. Other confiderations lead to the fame refuk. In the account which Sir W. Hamilton has given of the eruption of Vefuvius in 1794, Univ. Mag. Oa. 1795, it is ob- ferved, that " after every eruption of that volcano we read of damage done by mephitic air, which coming from under the an- cient lava, infinuates itfelf into low places, as cellars and wells hear the foot of the mountain." Several inftances happened af- ter the eruption of 1767, of perfons going into cellars and being ftruck down with this vapor, who would have died, without af- 333 fiftance. This vapor on an open plain fubfides near the earth, being heavier than common air ; but it fills cellars, wells and hollow places, fo as to endanger life, and aaually proves fatal to birds, beafts, and vegetables ; fometimes to men. This vapor or fixed air is generated by the aaion of vitriolic acid on calca- reous earth ; and by other means in the immenfe laboratory of Nature's works. The feas here ftated and which are well known to every chymift, will perhaps account for the damps in wells, as this fixed air is called in popular language. It is a common idea that air will become impregnated with this vapor, by mere ftag- nation in a well. This is probably a miftake. Nor is it proba- ble that any fubftances in the well generate this air. It cannot proceed from water, nor from the earth, or ftones, or rocks which compofe the fides of the well, unlefs the earth is different from common earth. It is probable therefore that this mephitic vapor is expelled from the earth by force of internal heat or elec- trical fire ; and that this happens not uniformly, or at any certain times. I fufpea that the difcharge of it happens at particular times in various parts of the earth, from caufes not yet explain- ed ; and that it occafions epidemic difeafes among men, beafts and fifhes. To aid us in an enquiry of this kind, it would be neceffary to examin a great number of feas, and difcover whether this mephitic vapor is ever found in wells, except when epidemic difeafes of fome fort or other prevail among animals. On the 30th of Auguft 1795, juft after the peftilential fever appeared in New-York, two men fell viaims to this vapor, in a well belonging to a brewery in Pine-ftreet, within a few yards of the houfe wtere I then refided. The well had been dug but a few months, and was not ufed, but covered over with boards. It was about 25 or 30 feet deep, contained a few feet of water, and was fo full of mephitic vapor, that a candle was extinguifhed within eight feet of the furface of the earth, as I found by ex- periment. This was during the ficknefs, and a queftion arifes whether the two things were conneaed in caufe. Had not a fimilar vapor been filently thrown from the bowels of the earth, over all the coaft and region from New-Jerfey to Conneaicut, 334 for fome months previous ? And may not the ficknefs of the oyfters and fiiad on that coaft, from 179410 1796, as well as the deftruaive epidemic angina, fevers and dyfentery, be afcrib- qd to .that caufe I I offer this hint to excite enquiry. Gov. El- lis, in a paper on the fubjea of hurricanes, Mufeum, vol. 9. i 15, mentions, among the precurfors of thofe tempefts, thick vapors in the air " fenfibly mephitic." If this vapor is the caufe of cUfeafes, it will account for the greater prevalence of* them in low fituations. There is reafon to fufpea that this mephitic air is expelled from the earth, in confiderable quantities, at particular times,: but incorporating itfelf with the common air, it does not often prove fatal to men, altho it may leffen the vital powers of the atmofphere, and aid in the produaion of difeafes. ' In 1729, on the 19th of July, a Mr. Adam? of Bofton and his fervant perifhed by this air in a well. Let it be obferved that in this year, the influenza fpread over Europe. Whether it was in America or not, I cannot learn ; but the meafles was epidemic in Bofton, in that year ; and other parts of America Were fickly. But what am<>ng other things inclines me to the opinion that this fpecies of air is not generated gradually in wells, but is ex- pelled from the earth fuddenly, is a faa related in the fame pa- per with the foregoing, Baddam's Mem. vol. 9. 4. Phil. Tranf. 411; that on the 9th of May preceding this accident, two men at work in a well in School-ftreet, Bofton, were fuddenly at- tacked by this fpecies of vapor, and came near lofing their lives. The well had recently been dug and enlarged, the workmen ex- periencing no inconvenience ; and that the vapor did not proceed from opening a new chafm, or breaking a new ftratum of earth or minerals, is certain ; for the men were not then digging, but ftoning the fides of the well. In Philofophical Tranfaaions, No. 119, it is faid that damps are generally obferved to come about the end of May, and to continue during the heat of fummer. At that feafon alfo they are moft violent in mines infefted with them, during the whole year. But by a fubfequent paragraph, it appears that the writer 335 in that remark made no diftinaion between fixed air and inflam- mable. =,. If it is true that this vapor is expelled from the earth in fpring and fummer only or principally, to what caufe fhall we afcribe that circumftance ? Not to internal heat certainly, for that at the depth of 20 feet is always the fame. We may perhaps find a folution in the excited atmofphere of fummer, which may oc* cation difcharges of ekaricity. It might be well for the world, if experiments were made to afiertain thefe points. If a vapor is at times thrown into the at- mofphere from the internal parts of the earth, and becomes nox- ious to health, it is of great confequence to the world to know . the fea, as this air fubfides into the lower grounds, and might. often be avoided. A deep covered well and not ufed, might be kept for this purpofe, and a lighted candle or lamp let down to its bottom once a month. If there had been a difcharge of me- phitic air, it would be found in the well ; but if the air of the well fhould be found good, we might conclude that the atmof- phere had received no taint from fubterranean vapor. This fubjea deferves inveftigation. The herbage is at times affeaed by a dew or clammy fubftance, which is vifible, tangible' and offenfive to cattle. Inftances have been related in the pre- ceding hiftory. The honey-dew is a curious phenomenon, not: well underftood. This is a fubftance that refembles honey or wax, depofited on the leaves of trees, and attaching itfelf to blades of corn. It is fweet to the tafte, and the honey-bee ie feen to feed upon it. To corn it is very prejudicial, by caufing a blaft. I have not been able to afcertain whether this is a periodical or an accidental phenomenon, nor to find the caufes of it in the known properties of air or water. Is it the produce of a vapor from the. earth ; or of fome unufual combination of aerial fub- ftances ? Wc live in a fluid, compofed of various ingredients, each of which has its own properties, and, by various combinations, an<* IneefTant changes, thefe ingredients are daily generating new prop- erties. One day, the fky is calm and cloudlefs; the next, the 336 heavens are wrapped in vapor, and the earth deluged with rain. One moment, we are fhrouded in chaotic darknefs ; the next prefents to us the heavens and earth in a fheet of livid flame. In- ftantaneous is the tranfition from the filence of the grave to peals of thunder that fhake the earth beneath our feet; and. the field that fmiks with its golden fruits, to day, is to-morrow torn with the raging tempeft, ftripped of its beauties, and converted into a barren wafte. Immerfed in elements produaive of thefe fudden and tremen- dous effeas, how is it poflible that man fhould pafs through life without feeling inconveniencies from principles capable of fuch af- tonifhing viciffitudes ? Inftead of wondering at the phenomenon of peftilence and other epidemic difeafes, and hunting, with mi- crofcopic view, for a bundle of clothes in which to find the germ of a malady that defolates the earth, men would fhow more wif- dom and more correa underftanding, if they would colka feas, with care, examin them with candor, and endeavor by this pro- cefs to arrive at fome knowkge of the powers and effeas of thofe elements which compofe all animal bodies, and from whofe ope- rations are immediately derived all the vital energies. There we may find, altho we may not be able to comprehend, principles of difeafe as powerful and as univerfal as the laws of nature. 337 On the revolution of certain Comets. SINCE this work has been in the prefs, I have had tho curiofity to trace back the revolutions of two or three comets, whofe periods were calculated by Dr. Halley, to find how far his aftronomical calculations are verified by the hiftory of the ap- pearance of comets, in former ages. The following are the re- fults. The comet of 1682 Dr. Halley found to have a period of 75 years. If this calculation is exaa, the fame comet muft have appeared in the following years. The firft column contains the years when the comet muft have appeared, fuppofing its period to be exaaly 75 years—the fecond, contains the years when a comet appeared, according to the preceding hiftory. A. D. A. D. 856 1757 ■-" " *757 1682 — 1682 | 781 1607 — --- 1607 706 l53l --- --- 153' 631 i456 --- --- 1456 | 556 1380 --- — 1380 1 481 1306 --- — i3°S 1 1 406 331 256 181 1Z31 —-' 1 1 1 rift t ... .- 1 1 1006 —— 1 — 1005 106 931 --- 1 3i I have found no mention of a comet in 1231, 1156, io8|, 031, 781, 706 ; but the phyfical phenomena at thofe periods, as fevere winters, inundations, earthquakes, peftilence, &c. ren- der it more than probable that a comet was vifible, in thofe years, or in the next preceding or following. In fome other periods, a comet is mentioned in the next year, to that which is defignat- VoL II. T t 858 784 632 556 or 8 480 407 181 33« ed in the firft column ; but I take this difference to proceed from the fraaions of a year—the period of the cornet not being exaaly a year. If thefe calculations and feas may be relied on, this comet Biuft have appeared in the year 256, in the midft of the mortal peftilence, in the reign of Gallus and Volufian, and in the year 41 or 32, a little before the crucifixion of our Savior. The calculations refpeaing the return of the comet of 1661 coincide remarkably with hiftorical feas. Its period is fuppofed to be 129 years. If fo, then it muft have appeared in the years named in the firft of the following columns—the fedond column contains the years when a comet did aaually appear, according to the hiftory in the firft volume. A. D. 1790 1661 1532 1403 1274 1145 1016 887 758 629 1661 *532 1402 1274 "45 1017 759 A.D. 500----- 502 371 ----- 242 ----- 113 ----- Before Chrift. 16 ------- i45 ------- H5 or 7 274 ------- 403------- I have no account of a comet in 887 ; but in page 112 of Vol. I. a fevere plague and hard winter are mentioned, under that year. The events related in page 77, under the years 242 and 3, are fuch as lead me to fufpea a comet, at that period, which correfponds with the calculations ; but I have no account of any. The fame remarks may be made refpeaing the events of the years 114 to 117, when Antioch was deftroyed, as re- lated page 70. Of the events before Chrift 16, I have no particular account. The three preceding periods of this comet, before Chrift 145, a 74, and 403, correfpond with great peftilence. See pages 42 339 and ^j__48__56 of Vol. I. And this might have been the ftar alluded to by Juftin, in the paffage quoted in page 43. But we have an infuperable difficulty to thefe calculations—this ftar, if its period is 129 years, fhould have appeared in 1789 or 90 ; but no comet was feen. One appeared in the autumn of 1788, but I know not whether the elements of its trajeaory correfponded with thofe of the ftar of 1661. Calculations of this kind are yet too uncertian to be the bafis of a fyftem. It is greatly to be defired that the revolutions of the comets could be reduced to as much certainty, as thofe of the planets. Such calculations would enable as to account for many of the vi- olent changes on this globe ; and aid us to fix the era of certain great phenomena of antiquity : For no fea is better eftablifhed, than that comets have a prodigious influence on the ekaricity of the earth and its atmofphere. The comet of 1680 is fuppofed to have a period of 575 ; and the appearance of a fplendid ftar of this kind in 1105 and 531, gives reafon to believe the calculation juft. If fo, it muft have appeared before Chrift 44—619—1194—1769 and 2344. The latter year falls within 8 years of vthe period affigrted to the del- uge. But the uncertainty of ancient chronology leaves room to queftion all refults from thefe calculations. 340 POSTSCRIPT. X N the courfe of my investigations into the origin of the bilious! plague, I have had fo many opportunities to detea the errors pro- ceeding from common report, that I am led to queftion every fa& that does not come direaly from the perfons concerned in the tranfaaion related. I had fuch confidence, for inftance, in the faas publithed and believed by the people in New-Haven, re- fpeaing the origin of the fever of 1794, in that city, from im- ported fources, that I had prepared an account of it for the prefs, before I called on the perfons beft able to give me correa information. On examination, I was forprifed to find moft of the fuppofed feas totally unfounded; and Mr. Gorham and Capt. Truman, the perfons concerned, when informed of the reports which had been circulated on the fubjea, expreffed their furprife that people fhould have propagated fuch tales, without Calling on them for a true ftate of feas. It was faid and publithed that Polly Gorham, the fecondfer- fon feized with the fever, was prefent in Mr. Auftin's ftore when the cheft of clothes was opened. The gentleman who publithed this report, has fince informed me that he had no authority for it, but the ftory of a child of fix or feven years old. But Capt. Truman who opened the cheft himfelf informs me, that Polly Gorham was not in the ftore at the time. It was reported and is ftill believed, by moft of the people in the town, that Ifaac Gorham's wife wafhed infeaed clothes ; but Mr. Gorham affures me that there is not the leaft foundation for the ftory, and he is aftonifhed that fuch a tale could have been circulated. He cannot atfign any good caufe for the fever in his family, and is inclined to the opinion that no infeaion was received from the floop. It is poflible and probable that fome perfons who came in the 34* floop had been into Gorham's houfe; at leaft into the fliop in the front room. And this is the only poflible way to account for the propagation of infeaion from that floop, even admitting that it contained infeaed clothing. But even in this cafe, it would feem Arrange that Gorham himfelf fhould efeape, and his] wife and niece who were ufually in the back room, fhould con- traa difeafe. But the following feas which have been^e- ceived from Capt. Truman, fince the firft volume was printed, will fhow the improbability, if not the impoflibility, of fuch a communication of infeaion. This tloOp, called the Iris, arrived from Martinico at New- York in May. All her men and paffengers were and had been, during the pafTage, in good health. The floop of courfe was permitted to enter as a clean veffel, and the was hauled up to a wharf, where the lay ten or twelve days wind-bound, before the could proceed to New-Haven. She had no cargo on board, except a few faked hides, which were taken out and .put on board of a coafter, commanded by Capt. Miles to be tranfported to New-Haven. This was done without the leaft injury to any perfon concerned in removing the hides. At this time happened along feries of eafterly winds and rainy weather, fucceeding the memorable froft after the 17th of May 1794. In thefe rains the veffel was wafhed inceffantly day after day, and the was vifited by many perfons who had bufinefs on board ; and as it happens with all veffels that lie at a wharf in fuch a place, hundreds, if not thoufands muft have been on board, while the lay at New-York. Now it happens that not a foul among all that were on board, from the time of her leaving Martinico, till the arrived at New- Haven, was affeaed with fever. How the floop or the hands, after having intercourfe with fo many perfons, came to referve their infeaion for New-Haven, I fubmit to be determined by wifer heads than mine. The faas are here ftated from the in- formation of the perfons Concerned—thofe which have been be- fore publithed, are mingled and confounded with popular rumors which can be traced to no genuin fources. Let it be noted that when the two firft perfons were feired, no perfon fufpeaed the difeafe to be the yellow fever. Mrs. 34* Gorham probably died without ever knowing her difeafe—at leafV her phyfician did not fufpea it, till fhe vomited black matter, the evening, before her death. Hence it happened that no enquiry into the origin of the fever, took place till feveral days after- Wards, and not till after the death of Mr. Auftin and his clerk. This is one reafon why it became difficult to obtain a true ftate of feas—a difficulty that was greatly increafed by the alarm and confequent perturbation of the public mind. And after all the queftion of domeftic or foreign origin is much better decided by the charaaer and phenomena of the epidemic, than by any human teftimony relating to things not vifible. The cafe of a bilious fever, attended with black vomit, men- tioned in page 3C6 of Vol. I. occurred in the laft week in March, near the wharf and in the center of the ground, afterwards the feat of the fever. It was lefs malignant than in autumn, but from the defcription of it given me by the woman's mother'and the attending clergyman [the phyfician being dead] I muft con- clude the difeafe to have been of the fame fpecies, and indica- ting a difpofition in the atmofphere of the place to give to fever that particular charaaer.* The fcarlatina was then the current epidemic. In May this declined, and gradually difappeared, in June and July, as the yellow fever advanced. To a philofophic mind, thefe fexls amount to evidence of domeftic origin, that far out-weighs the uncertain and contradiaory evidence of the importation of a fubftance which is neither vifible nor tangible. With refpea to the origin of the. fever at Hartford, I have this further evidence. The floop mentioned in page 347, had never been in the leaft infeaed with, any difeafe whatever, before foe arrived at Hartford. Her former Captain died in May of a lingering complaint. Pie went to New-York after he was unwell and growing worfe, he returned and died at home. Captain Tucker then took the command, went to New-York and took onboard a cargo of felt. From thence he failed to New-Ha- ven, where he lay five or fix days, at the wharf^ endeavoring to * The phyfician, Dr. Hubbard, after the fever appeared in fummer, mentioned to the Rev. Mr. Hubbard, that it was of the fame fpecies with that which occurred in March. This cafe was nine or ten weeks before the arrival of the Iris. 343 fell the fait. 'While there,people indifcriminately were onboard, and among them feveral gentlemen of my acquaintance who give me this information. This was about the middle of July, and as it was jftft after the Neptune arrived from China, the wharf was unufually crouded with people, who were paffing and repaf- fing between the wharf and that fhip. Here then the floop did no mifchief,,.. She went to Hartford and difcharged her fak. I have unequivocal evidence that not a perfon concerned in un- loading her, was affeaed with fever, and that feveral of the per- fons firft feized in Hartford, had not been near her. After the left Hartford the captain and mate were feized, and the former died f_not both as ftated in page 347.] Another veffel, I find, has by fome been fufpeaed of introdu- cing the fever into Hartford. This alfo was a coafting veffel, which took in a paffenger at New-York, who fickened, after he came on board, and the mafter landed him at New-Haven. If I am rightly informed, this veffel did not arrive at Hartford, un- til after the firft cafes of fever occurred ; but of this I am not certain. Certain it is, that no perfon on board, except the paffen- ger landed at New-Haven, was ever ill, and therefore the cafe deferves no confideration. It ought further to be ftated that two or three weeks before the alarm at Hartford, and before the arrival of thofe veffels, a cafe of fever occured of the malignant kind, and in all effential points, with the charaaer of the yellow fever. I have lately learnt that a fimilar fea occurred in Bofton in 1798. Thefe cafes are not ufually numbered with thofe of yellow fever—but the truth is, and fuch will it appear to be, when fcience, philofophy and candor fhall triumph over prejudice and popular tales, that thefe milder cafes of fever, bearing the charaaer in a degree, of the fubfequent epidemic, are the precurfors of the difeafe to fol- low—they are the effea of the atmofpheric principle on partic- ular fufceptible conftitutions, before the proper feafon for the full force of the principle to operate—they are irrefiftible evidence that the difeafes which they precede, are ufually, if not always, generated in the place where they exift, 344 SINCE the firft volume was printed, I have obtained from attending phyficians, an account of the fever at Middk-Haddam, in the town of Chatham, on Conneaicut river in 1796. [This is mentioned in page 331 to have been in 179 7, but it was in 1796.] This fever was traced in every inftance to a veffel from a port in Hifpaniola, which was highly infeaed. No perfon was af- feaed, without direa intercourfe with the veffel, the clothing or the fick. About 30 perfons were affeaed, eight of whom died. When carried to a diftance, the fever did not foread. That this was a difeafe contraaed from imported infeaion is evident from this ckcumftance—that in every cafe it could be traced to intercourfe with the fick or infeaed articles—it was not taken by patfing along the ftreet nor from houfe to houfe. A- nother faa is equally demonftrative of this origin ; which is, that it commenced late in September and had no precurfors.' When it arifes from the atmofphere of the place, it always be- gins as early as Auguft or earlier—and this is probably true of every autumnal complaint in our latitude. The fever in that place therefore was what I call a difeafe of mere infeaion, in contradiftfoaion from yellow fever originating in the country, which begins uniformly in the hot months, is taken without intercourfe with the fick or with infeaed articles, has its precurfors and abforbs all other difeafes or gives them all its predominant type. The diftinaion is fo obvious that it is not eafy to miftake it, Of the difeajes from imported fources, this is one—two Qr three other inftances in the United States have been mentioned. But moft of the inftances of this fever in America, fince 1790, have had the unequivocal charaaers of epidemics—fuch charac- ters as never attend, and as cannot poflibly attend, difeafes of mere infeaion. IN the fummer paft, the wild pigeons in the weftern parts of New-York ftate and in Pennfylvania, have been affeaedwithadif- eafe of which many have died. It is underftood that the head or peck was fwelled; but I have no correa account of the diftemper. 345 FROM the report of a mafter of a veffel, it appears that fifh of various kinds perifhed in September or Oaober laft, on the Carolina coaft from Cape Look-out to Cape Fear, a diftance of 70 miles. Some were feen dead and others dying, as far as the eye could reach. The yellow fever has alfo prevailed in fome parts of both Carolinas. Does not the death of fifh afford reafon to believe that the ekarical fluid or mephitic air, is occa- fionally difcharged from the earth in unufual abundance ? And may not local difeafes be afcribed to that caufe ? IN addition to what I have faid in the 16th feaion, rela- tive to predifpofition to a particular difeafe, I would obferve, that we ought to make a diftinaion between a natural aptitude to a difeafe, and an adventitious liability to it, from artificial caufes* The latter is what ufoally paffes under the name of predifpofition c And this may lead to error. When perfons fay, a man will not take a fever by infeaion unlefs he is predifpofed, they ufually mean that he has, by accidental caufes, prepared his body to be affeaed. Hence we continually hear the doarin that infeaion will not operate in a healthy atmofphere ; but in order to give it force and effea, the atmofphere muft be prepared ; that is, mufl fuffer a change favorable to a difeafe, but not fufficient to pro- duce it. I apprehend this doarin is erroneous. The h&, as a gene- ral one, is the reverfe ; and the longer a body remains in health in an infeaed atmofphere, the lefs liable is it to the difeafe. So true is this, that prifoners in jails fuffer no injury from the air, which will deftroy the lives of men who enter it, from frefh air. This fea is well known. It is equally true, in our cities, du- ring peftilence, that perfons from frefh air, are much more liable to be feized, on entering the infeaed atmofphere, than' thofe who have lived in it. Hence in every cafe of mere infeaion, perfons are mofl expofed to it, who are leafl prepared or predifpofed by breathing an infeaed air. But not fuch is the fea with regard to the influence of atmof Vol, II. U u 346 pheric caufes on particular bodies. In this cafe, the caufe fingles out and feizes the perfons, who have a particular aptitude or habit of body, in a manner altogether unaccountable. Sometimes this power is evidently in operation a long time, before it pro- duces difeafe. Perhaps this natural aptitude of a body to receive or refift difeafe, may be illuftrated by the following fea, which is under every man's obfervation. Let two apples or pears, be taken from a tree at the fame time—let them be apparently alike in foundnefs and in every particular on which their prefervation may be fuppofed to depend. Lay them by the fide of each other—equally expofed to heat and moifture. In this cafe, one may and often will perifh many weeks before the other. This aptitude to perifh is natural, and doubtlefs confifts in the interior organization of the fruit ; but this is utterly invifible, even with the beft microfcope. This idea feems to be important towards accounting for the operation of a peftilential atmofphere on various bodies, and is confirmed by the feas related of peftilence that has feized par- ticular families or tribes of men, while others, equally expofed, have efcaped. This may be called natural predifpofition or ap- titude to a difeafe, in diftinaion from that ftate of the body which is the effea of artificial or accidental caufes, and which may be the commencement of the difeafe, according to Brown's definition. SINCE the firft volume was put to prefs, I have colkaed from various authors, accounts of feveral plagues in Egypt, which I had not tlien found. As I have fuggefted that pefti- lence is ufually marked- by catarrh, it may be proper to lay to- gether further evidence of the fea. Egypt and Conftantinople are the places where autumnal fevers are moft apt to take the form of peftilence. Catarrh, in thofe cities, feems clofely to attend the plague. Witnefs the following examples. A. D. 1580 influenza. 1581 deadly plague in Egypt.. r347 ?27 n J general plague. A. D. 591 influenza. 59' 593 597 influenza. 5981 599 {► general plague. 600 J 602 influenza. 603 plague. 610 influenza. 6nT , r deadly plague in Conftantinople, &c 693 influenza. 694 plague in Egypt. 699 influenza. 700 plague in Egypt. 712 influenza. 713 plague in Egypt. 717 influenza. 7*7') 8 f plague in Egypt and Turkey, &c. 7261 728jPlagueinEgypt' &C* 729 influenza. 732") C plague and influenza. 7333 F & 736 plague deadly in Egypt. 737 influenza. 738"! deadly peftilence in Weft-Indies, Mexico, Ock- 739 j zakow, &c. 743 influenza and plague. 744 influenza. 745 plague in Egypt. 758 influenza—plague began. 759 plague in Egypt. 762 influenza and plague in the Levant. #8 A. D. ' 1767 influenza. 1769") r plague in Conftantinople and Egypt. 1782 influenza. 17831 1784 J» plague in Egypt and Afia, 1785J 1787 plague in Afia and Africa. 1788 influenza in Europe. 1789 influenza in America. 1790 influenza in America. 1 began peftilence in America, and Weft-Indies which J has not yet ceafed. Severe plague in Egypt. There are feme long periods in which I have no account of the difeafes. The plague of 1705 in Egypt is the only one of which I have an account, that I cannot trace to a conneaion with uni- verfal catarrh ; and I have no account of a plague in Egypt after the influenza of 1709. I afcribe this however to the imperfec- tion of my accounts. How greatly to be regretted is the want of accurate and complete regifters of epidemic difeafes ! Let this detail of authentic feas, be compared with what eve- ry man may recolka in America. How the prefent feries of plagues was introduced by a double portion of catarrh ! for the influenza of 1789 was followed in 1790 by another influenza— the only inftance I can find on record of two of thefe epidemics within the fhort fpace of fix or eight months ! Let it be recollec- ted alfo that catarrh was prevalent in the fpring of 1791,1793 and 1798, andthatin our large cities, peftilence has in every inftance,been introduced or followed [or both] by influenza, which has fome- times been local, that is, very much limited to the place where the peftilence had prevailed or was to prevail. Who then can deny that catarrh and plague are conneaed in caufe ? It is not pof- lible to deny it—the evidence is conclufive—and when this fub- jea fhall be fully inveftigated, it will appear that peftilence, whether plague or yellow fever, is produced by the fame general change fa the properties of the air, which produces influenza—the, tran.r 349 fttions from the one epidemic to the other being caufed bythe fea» fons, or other unknown caufe. I learn from a communication of the Britifh Conful at Alex- andria, that it was calculated a million of people had periftied by the plague in Upper and Lower Egypt between 1791 and 1796; ,and our accounts from that country, mention that the difeafe had not ceafed, the laft fpring ; that is, it returned at the proper feafon. It feems therefore that peftilence in Africa runs coterri- poraneous with peftilence in America. I have recently learnt from Irwin's Travels,'that there was no plague in Egypt fiom 1770 to 1777, and from other writers I colka that it was not there for two or three years after. This is a remarkable fea, as Egypt is feldom exempt longer than five years in one period. Now it will be remarked that in the fame period, and for fome time before and after, no epidemic infec- tious yellow fever occurred in America, nor as far as I can learn, in the Weft-India Iflands. Yet this was a time of war between Great-Britain, America and France.* But it is a curious fea, that in thofe parts of the earth moft fubjea to peftilence, the plague and yellow fever fhould have difappeared at the fame time; and in countries 5000 miles diftant, certain kinds of difeafes fhould have loft that peculiar charaaer which diftinguifhes the plague. But the hiftory of epidemics fornifhes numerous inftances of fimilar revolutions in the prevailing type or charaaer of difeafes. In Mr. Tytkr's Treatife on the plague and yellow fever, which I have juft read, I find a paffage, in page 379, which afferts that certain quotations in my letters to Dr. Currie in 1797 were made " with a view to difpute the contagious nature of the yel- low fever." This is not accurate. My view was to prove a me- terial difference in the yellow fever at different times, and to fhow certain inconfiftencies in the reafoning of my antagonift. * No comet was feen between 1770 and 1784—a period of more than thirteen years—fuch an interval had not happened within 15© years> and probably not in three centuries. 35® ' tt is proper now to mention that I wrote thofe letters, with A *iew if pofEble, to fettle the queftion of the origin of the yellow fever, by a fair ftatement of faas and fair conclufions from the faas. I had not then attended to the hiftory of epidemics J. and k will be feen by one of my letters, that I had embraced the popular opinion then current, that the influenza in 1789 and 1790 was a new difeafe. Since I have ftudied this fubjea, I am fur- prifed not only at my own ignorance, but at the ignorance of all claffes of men, in whatever regards the hiftory of epidemic difeafes, and the phyfical phenomena of the earth and atmof- phere. On this fubjea and whatever regards the origin of the plague and yellow fever, Mr. Tytler's Treatife has difappointed my hopes and expecTions. His hiftory of peftilence is from firft to laft imperfea and inaccurate. And how it is poflible for a man to fuppofe that the plague was originally fent upon the Jews as a punifhment, and by them has been conveyed to other nations, p. 47. or that the plague in Rome in the year 80 was occafioned by infeaion conveyed from Jerufalem, by the army of Titus in the year 70. p. 13. 45. 50. Or that it is of divine original, p. 369, any more than all other diftempers-—Or that it has been ufually propagated by war and commerce p. 369, when it is evi- dent from fcripture that it was a difeafe in Egypt, before the days of Mofes—«and has in every age infefted nations who had no in- tercourfe with the Jews—when alfo it is exprefsly declared by Livy and Orofious to have been ufually in Rome in time of peace—I fay, how it is poflible, in this period of the world, for fuch opinions to exift, I cannot conceive. On the fubjea of contagion alfo, or rather infeaion, Mr. Tytler, has adopted the common theory—a theory acknowkged to be inadequate to the folution of the phenomena of peftilence, as plague and yellow fever always ceafe, at the proper feafon, when the infeaion is moft general. The refults of my inveftigations will explain moft, if not all, the difficulties attending this fubjea. The origin of peftilence is traced to effential changes in the at- mofphere, which recur at certain unequal periods. The evi- dence of thefe changes are certain epidemic difeafes, as mealies, 351 affeaions of the throat, and efpecially influenza, which pervades the globe or large portions of it within a few months or at moft, in two years. Near the time of thefe phenomena, and ufually fobfequent to the influenza, the plague occurs in Egypt and Con- ftantinople, and if the change in the atmofphere is very great, the plague occurs in all parts of the Levant and in other parts of Africa, Europe and Afia. At the tame time, in the more cool and healthy regions of the north, epidemics of a milder type than the plague, but malignant and infeaious, prevail, and in fhort, ordinary difeafes affume new and more fatal fymptoms. In America, the fame or fimilar changes are obferved. The fe-: ver of the Weft-Indies, which is ufually not infeaious, becomes more malignant and affumes in a degree the charaaer of the plague. In our large cities, the autumnal remitting fever is changed into the fame malignant form, and the country foffers by meafles, fcar- latina, dyfentery, typhus and remitting fevers. Thefe changes ufually take place in both hemifpheres at the fame time; but fometimes the peftilential principle feems to be more fevere on one continent or in one country, than in another Thefe changes are ufually diftinguiflied by vifible and remark- able phenomena in the natural world. The periods of peftilence are unequal and indefinite—-fome- times of only five or fix years duration ; at other times, extend- ing to ten or fifteen years. But in the latter cafe, the epidemics mentioned ufually run through a country twice—that is, two peftilential periods occur, without an interval of time. During thefe periods, contagion and infeaion aid the propaga- tion of certain difeafes, particularly the meafles, fmall-pox' whooping cough and angina maligna. In the dyfentery, yellow fever and plague, infeaion has its effea and obvioufly fpreads the difeafes. But all thofe difeafes originate without infeaion, in all countries where the heat, moifture or other local caufe will permit the difeafe to exift. In fome cafes, they are introduced and fpread folely by infeaion, but they are then always within human control, and it is the fault of man, if the fphere of thek operation is not very limited. In moft cafes, thefe difeafes have the unequivocal charaaers of local epidemics, and no human power can reftrain them. 352 On the fubjea of cure, if I may be permitted to have an opin< ion, I fhould concur with Mr. Tytler in the preference of the diaphoretic method. Circumftances may indeed defeat this meth- od, and compel the phyfician to adopt others. But from the in- dications of nature, and the immenfe capacity of vapor to ab- forb heat, I take perfpiration to be the natural remedy for fever. On the fubjea of the proximate caufe of the plague, the opin- ions of Mr. Tytler are highly refpeaable. I fully agree with him in the influence of the ekarical fluid. I believe this aaive and elaftic principle to be the great agent in all the changes vifi- ble and invifible, in our atmofphere, and I cannot but think my inveftigations have unlocked very important fecrets on that point. I believe alfo that this fluid is the immediate agent in fupportiog life, and the intelkaual powers. Received into the lungs, it fupplies the body with heat, and by its elaftic power, dilates thofe organs of life to receive new fupplies. The machinery of the body is thus calculated, while it lafts, to preferve perpetual motion. At the fame time, this fluid, by the fame elaftic power, becomes the medium of fenfation, throughout the nervous fyftem, and by its inftantaneous motions, communicates fenfation and thought, with the celerity of lightning. New-Haven, November 1799. I M