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UNITED STATES OF AMERICA
WASHINGTON,  D. C
 
 
Ik/V^o" 
SKfTCH
OF THE
REVOLUTIONS
IN
'•■'*
tC   H   E   M   I   S   T    R   Y,
By THOMAS P. SMITH.
ljA.uit A III.  -   C
         PHILADELPHIA:

P-RINTED BY  SAMUEL H.  SMITH,
            Mo. 118, Chefnut llreet.
M,DCC,XCVIII. 
 
To ROBERT PATTERSON, A. M.
PROFESSOR OF MATHEMATICS IN THE UNIVERSITY 0l
              PENNSYLVANIA.
     Sir,

  I KNOW no perfon to whom my firft eflay can be
dedicated with fo much propriety as to the inftru&or
of my  early  youth.   Accept it  then  as a fmall, but
fincere, tribute of gratitude, from

             Tour friend
                     and pupil,

                  THOMAS  P.  SMITH.
C 

I
•
<l 
      PHILADELPHIA LABORATORY,
                             April  14th, 1798.

 In rmeting of the Chemical Society of Philadelphia,

   RESOLVED—That a copy of Mr. Smith's learn-
ed and ingenious Oration be requeued for publica-
tion.
        Extrad from the minutes,

                 GEORGE LEE,
                           Jun. Sec'iy. 
'i 
*
INTRODUCTION.
 Gentlemen of the Chemical Society,


    XXAVINft hern honoured by you with the ap-
pointment to deliver the annual oration, I have, with
diffidence,  prepared myfelf to comply with your re-
queft.  I (hall not attempt to apologize for any iiriper-
fedions  it  may  contain,   however numerous  they
may be;  as they  are the inevitable  effeds of  your
choice.  But there is one  liberty  I  have  taken, fox
which  I confider myfelt bound to apologize!.

  The Refolution, in purfuance of  which this oration
is delivered, direds that it fliall contain all the difco-
veries  made  in the fcience of chemiflry  during the
preceding  year.   Inftead  of complying  with  the
letter of this refolution, I  have taken the liberty of
preparing for you a fketch of the  rtvolut.ons in cbe~
tnijlry.   To this I have been induced from a confi-
deration of the utility and pleafure that always refult
from a knowledge of the origin of our opinions.   He
who fhould take up his abode on the  banks of a  dream,
and quench his thirftfrom its waters, could not feel un-
inverelted in a knowledge of its fource, and the courf*
                        B 
(  *   )
it has run.  Knowing over  what fubftances its  wai-
ters have pafied, he is  enabled in fome mesfure to
judge of their purity, and is put  on his guard againft
any bad effeds that may be produced by them.  Thus,
by knowing the origin of our  opinions and the channels
through which they have come to us, we can form a to-
lerable judgment of what particular prejudices they are
moft likely  to be  biafled by,  and  be  thus put  on
our guard againft receiving  them without the ftrideft
examination.  Such were  the  reafons which induced
me to write, and  which I  hope will induce you to
pardon me for delivering before you, a sketch of the
revolutions in chemistry. 
A
SKETCH,  «*.
    T
     X HE origin of chemistry,  like the origin of
every other fcience that early dawned upon mankind,
lies buried beneath the dark fables of antiquity.   The
afcription of the difcovery of truths, or the invention
of arts,  beneficial to mankind, to fupernatura; beings,
was  fo  general during thofe dark ages of ignorance
and  fuperftition, that we are not to wonder that the
fcience of chemiftry was fuppofed to  have had a di-
vine origin.

   If  mufic, poetry, and painting; if the arts of mak-
ing wine,  rai(ing grain,  healing  the fick, had their
tutelary deities who were fuppofed to have taught them
to man, if  the Egyptian, wLen  he beheld the Nile,
without any apparent caufe to him, who  was   igno-
rant of its  fource, periodically  overflow  its  banks,
fertilize his land, and then peaceably retire within its
proper limits,  fuppofed it to  defcend  from  heaven,
fhould  we  not exped that chemiftry, a  fcience to
which almoft all others  owe their birth,  would have 
                    (  »2   )'
been fuppofed to  have been  derived from the gods.
Accordingly we find this to be the prevailing opinion
of the ancients.   But however interefting an invef-
tigation of thefe  fables  may  be to fij^h as imagine
them allegorical accounts of the origin of chemiftry^
we muft pafs them over as  the unmeaning offspring of
jsnorance and superstition.

  Were  we to endeavour to fearch out the  true ori-
gin of chemiftry,  we fhould find ourfelves bewildered
to little or no purpofe among  the multifarious traditi-
ons of antiquity; like the traveller who fhould in vain
attempt to afcertain the true fource of  a great river,
formed by the union of a number of  fmall ftreams,,
we fhould after much  labour and difappointment give
up  the purfuit  a' one in which the effed produced
wowld not repay us for the labour endured.

   The Arabians appear to have been the firft people
who made any considerable  progrefs  in  chemiftry.
For however great the  extent  of knowledge in this
Jcience  the votaries of antiquity may afcribe to the
Egyptians, we cannot confider them as having  made
any great progrefs in it.   It is  true they had carried
fome of  the pradical  parts of it,  fuch as,  the work-
ing of metals, imitating precious (tones,  and paint-
ing on glafs, to a considerable degree  of  perfedionj
yet they  do not  appear to have pofiefied any know-
ledge of its general principles.  It was as yet confine4
to the forge  of  the  fmith and the work-Chop of the
lapidary ; and they expeded their  precedes  to termi- 
(  '3   )
nate favourably  only  becaufe their predeceflbrs, who
perhaps were taught by fome happy accident, promifed
them fuccefs.   Their priefts, indeed, pretended  to
extenfive  knou ledge in thi§ as well as in every  other
fcience, but as they have left us no data by which we
can judge of  their knowledge, we are led to believe
that in thefe pretentions,  as well  as in thofe to great
fandity, their objed was merely to gain an aicendency
over weak minds.   The {impleft ideas represented by
their hieroglyphick charaders were converted by the
eye of ignorance, who venerates every thing fhe does
not underftand,  into the moftfublime truths.  Hence
arofe  the  idea that thefe priefts, who perhaps under-
ftood  little more than how to delude  a  fuperftitious,
ignorant people, were poffeffed of  a knowledge  of all
the arcana of nature.

    Nor need we be furprifed that this was the cale in
thofe dark ages, when even in this  enlightened century
men are  found  weak enough to  fpend their time in
the folution of ancient fables, in fearch of truths  vvhich
are only to be  difcovered by contemplating the works
of nature, and who have the effrontery to declare that
in  thefe  puerilities they can  eafily difcern that  the
ancients were  pofleffed  of a knowledge of almoft all
that the  moderns have thought themfelves the difco-
verers.  So far, indeed, has this blind  attachment
to antiquity been carried that it need not excite your
iurprife,  if fome one of thefe fabulous  commentators,
more deeply learned than his fellow labourers, fhould
by  means of a fmoaking chalice found on the pillar of
Trajan, transfer  from Wvoisier to an Egyptian  prieft 
(  u   )
the honour of the pneumatic theory ;  or, by the bowl
of the  facrifice  overflowing with blood, painted on a
Mummy, deprive Priestley of the honour of the difco-
very of the oxigination ol the blood.

  To the Arabians, then, is tobeafcribed  the honour
of being the firft nation  in which chemiftry ceaied to
be nothing more  than a knowledge of a few proceffes in
the arts confined to the work-mops of illiterate me-
chanics.   To this nation we are indebted for its ap-
plication to medicine which was fiift effeded  in the
tenth century by Rhafes a phyfician of the hofpital of
Bagdad. • It now became an objed worthy the attenti-
on of men of letters and' genius.  The  phcenomena
of nature were fcrutinized with an attentive eye, new
proceffes were inftituted for determining her laws,
and  bodies before fuppofed fimple, were analized by
means of newly difcovered agents.  Such was the fitu-
ation of chemiftry in Arabia, when by means,  appa-
rently little favourable to the diffemination of fcience,
it was tranfplanted into the weft, of Europe.

  Towards the clofe of the eleventh century all Chrijl-
endom was roufed to arms by the declamation of an ob-
foure individual  of the name of  Peter, firnamed the
Henuit.   This  man, who to the moft barbarous fere*
city added the  moft  refined cunning, travelled over
Europe preaching up a croifade to recover from the
hands of the infidels the holy-land.' As his hearers were
plunged in the  moft  barbarous ignorance,  their paffi-
6ns were eailly wrought  upon,  and this man who in
the  eighteenth  century  would be confined in a mad- 
•(  '5   )
houfe, or treated with contempt, in the eleventh raifed
an army of ;oo,ooomen to effed his abfurd fcheme.
This army of which bigotry and superstition led the
van, and murder and rapine clofed the rear, was com-
posed of men of every rank and profeftkfn.  And this
army, however unfit  a  medium it may appear for the
tranfmiflion.of fcience, was the means by which che-
miftry was firft  tranfplanted  into Europe.

  That men aduated  by fuch motives as the croifa-
ders were, who, with the fymbolsof peace in one hand,
and a reeking  fword  in the other, marked their foot-
fteps with  the blood of women and children ; who had
left their peaceful habitations',  their wives, their chil-
dren and all the joys of domeftic happinefs, to  enforce
by the fword the truth of a religion whofe bails is cha-
rity,  and  to wreft from the hands of infidels,  in ano-
ther quarter of the world, a barren trad of land almoft
unfit for the habitation of man, becaufe it was the birth
place of their  religion ; that thefe men fhould be the
diffeminators of fcience, is a  paradox in  the biftory
of the human mind that at firft view appears inexpli-
cable.  But  the difficulty vanifhes when we recoiled,
that,  happily for the caufe  of fcience, the chemiftry
of the Arabians wis deeply tinged with alchemical no-
tions*.  The croifaders who were blind to the charms
of fcience, were far  from being fo  to thofe of gold.
As foon, therefore, as chariQt threw in their way pre-
tenders to the  art of converting the metals, their ava-
rice was roufed, and for the lake of the promifed wealth

              * See note A. at the end. 
(  16   )
they condefcended to ftudy chemiftry.  After the de-
feat of this immenfe army, many, who had fet off with
a defign of converting the infidels to Chriflianity by
means of the fword, returned to endeavour to convert
all the metals into gold  by means of their newly ac-
quired chemical agents.

  Europe foon fwarmed  with people in fearch of the
agent, by means of which the bafer metals were to be
converted into gold and  filver, and to which they had
given the name of the Philofopher's-ftone.  All claffes
of people were feized with the mania.   The indigent
man, who was initigated  to ftudy by the hopes of ac-
quiring wealth, but who  for want of money to com-
mence his operations was unable to proceed, was fure
to find a  patron  among  the wealthy, who upon the
condition of fharing in the difcovery, advanced large
furas of money for carrying on the operations.  Pro-
ceffes of the moft extenfive and expenfive nature were
inftituted in fearch of this chimerical fubftance, and
the moft important difcoveries, though different from
that moft hoped for, were made.  No expence of la- ,
bour or time was fpared, and immenfe fortunes were
difiipated  by men who would not have advanced the
fmalleft fum for  the  difcovery of any truth whatever
from which they could not hope to derive fome pecu-
niary advantage. Thus was avarice eniifled in the caufe
of fcience,  and  thus  that word paffion of the human
breaft, which has ever, but at this tingie period, re-
tarded the progrefs of fcience,  now tended in the moft
aitonuh.ng manner to its promotion. 
(  '7   )
  That branch of chemiftry called mineralurgy,  par-
ticularly flouriihed  during thefe refearches. The me-
tals were the objeds to which the attention of the al-
chemiftswas immediately direded. Hence conliderable
progrefs was made  in the art of  extrading them from
their ores and working them.

  From an idea entertained by fome of the alchemifts
that the philofopher's-ftone was to be the refult of an
intimate  union of fulphur  and  mercury,  this femi-
metal became in a peculiar manner the objed of their
attention.  The refult  was  that the materia medica
became enriched with  many invaluable preparations
of it.

  This period  gave birth to a number of men of the
moft refpedable talents; at the head of thefe we muft
rank  Roger Bacon, who flouriihed in  the thirteenth
century, and whofe mind was deeply tinged with  al-
chemical  notions.

   In  the courfe of fome chemical experiments, Bacon
having mixed  nitre, fulphur and charcoal together,
in a mortar, they by accident took fire and produced a
loud  explofion, this firft fuggefted to him the idea of
making gun-powder, which,  from a falfe idea he en-
tertained  of the terrible  effeds that would be produced
by  its being generally known, he concenled in his writ-
ings under the form of an anagram.

   In the fixteenth  century a new fed of alchemifts
appeared, who were in feach of a medicine that fhould
cure all difeafes.
                          C 
(  18   )
   'thb Arabians in their trealifes on alchemy, had em-
 ployed that figurative language which  is fo univerfal in
 the Eaft.  The agents  they  ufed for bringing metals
 to perfection they called medicines, the imperfetl metals
fick men, and gold a found, lively, 'healthy, durable man.
 When the  Europeans procured tranflations of thefe
 works many of them underftood all thefe figurative ex-
 preflions  in a literal fenfe, and when in the courfe of
 their reading they met  with paflages like the following
 from Geber, "  Gold thus prepared cures lepras, cures
 all difeafes? and  in  which  he only meant it would
 tranfmute all the other metals into gold,  they under-
 ftood it to be a medicine by which all the difeafes to
 which the human frame  is  liable  might be  cured*.
 Such was the origin of a fed of alchemifts to whofe in-
 duftry we are indebted for the moft valuable acceflions
 to the materia medica.

   At the head of this fed  of alchemifts flood Paracel-
 fus, a name familiar to every chemift.   He was born
 near Zurick in Swifferland, in 1493.  From hisearlieft
 youth he feems  to have  poffeffed  all that wildnefs of
 imagination which fo flrongly charaderizes his coun-
 trymen.   The  moment he conceived a thing poffible,
 he formed a theory for  the performance of it, and then
 proclaimed to the world he had effeded it.  As foon,
 therefore, as he conceived of the  pofiibility of forming
 a panacea, he commenced his fearch after it, and em-
 boldened  by the fuccefs of fome of his  mercurial- pre-i
* Boerhaave. 
(  «9   )
parations he declared he poffeffed the power of clofing
forever the door of the tomb.

  Having  likewife  formed  an idea of a liquor  that
fhould diflblve every fubftance in nature, and to which
he gave the name of  the alcahefl,  he dectar d to the
world he had  difcovered it, and publiflied a book, in
which he gave an account of many  of its operations.
This book abounds with the wildeft extravagances and
moft palpable contradidions.  In  feveral paffages of
it he tells us of his having diffolved various fubftances
in  the alcahefl,  in veffels  hermetrically fealed, in
which operations although the fubftances were readily
diffolved, the  veflels appear to have remained undif-
folved by  this univerfal folvent.   Van  Helmont has
likewife written much on the alcahefl, and has the ef-
frontery to declare that he poffeffed for a confiderable
time a vial containing  this wonderful liquor, but that
it was given to him, and afterwards taken away from
him.

  In addition to the panacea and alcaheft, Paracelfus,
declared himfelf poffeffed of the philofopher's-ftone.
Thus he perfuaded  the greater part of  his cotempora-
ries that  he was  pofleffed of what they conceived the
two greateft  bleffmgs man can  enjoy,  the  unlimited
pdwer of encreafing  his wealth and prolonging  his
life.   Againft the truth of an opinion fo generally en-
tertained by his cotemporaries, we fhall offer but one
objed ion.  Paracelfus at the  latter end of his life wan-
dered about Europe in poverty, and died at the age of
48, to  the difgrace  of his boafted aurum potauiie, 
(  *°   )
azophs,  little demons, elixers, and immortal catholi-
cons,  after a few days ficknefs at a public inn at Saltz-
burg,  although he had flattered himfelf that by the ufe
of his elixer proprietatis he fhould live as long as
Methufelah.

  The failure of Paracelfus did not intimidate others
from purfu'ng the chimera,  among the  number, Caf-
fius, known by his precipitate of gold ; Libavius, v\ hofe
name is affixed to a preparation of tin;  Sir Kenelm
Digby, who believed in the fympathetic adion of me-
dicaments ;  Van  Helmont  famous  for  his medical
opinions  and chemical notions;  and Borrichius a
Danifh chemift, who firft difcovered the method of in-
flaming the oils  by the nitric acid, are particularly to
be noticed for their talents.  To the labours of thefe
men we  are  indebted for many valuable  medicines.
But in a peculiar manner they demand our gratitude
for the intimate  union they have produced between
medicine and chemiftry, the confequence of which has
been  that difeafe has been ftripped of half its terrors.

   Amid the dark gathering clouds of ignorance and
fuperftition, that hung over all Europe during this cen-
tury, one ray of light burft forth fo pure and ftrong as
to indicate a rapid difperfion of the worfe than Egyp-
tian darknefs of  the age.  Francis Bacon, a name that
muft  at once draw forth our pity and admiration, ap-
peared at the latter end of the fixteenrh century, and
 laid  the  foundation of  natural  philofophy on  the
true and immutable balis of reafon.   For fome centu-
ries paft the world had been engaged not in difcuffing
philofophical truths, but the opinions of philofophers. 
(  21   )
The book of Nature, from whence alone true know-
ledge can be drawn, was entirely negleded,  and the
works'of Ariftotle and Plato were  marie ufe of to fup-
ply its place.  Inftead of endeavouring to difcover her
laws by obferving their effeds, they attempted to ex-
plain them  by the  categories  of  the Peripatetics  or
the ideas of the Platonifts. But Baccn, perceiving that
thefe ignesfatui only ferved  to lead ailray,  chofe for
his guide the invariable light of reafon.  By this he
foon perceived that a knowledge of the laws of Nature
can only be acquired by obferving her operations.  He
therefore advifed rhankinH, inftead of fpending then*
time in interpreting the idle dreams of myftical philo-
fophers,  to forfake their air-built caftles and by expe-
riment ered their fyllems on the adamantine bafis of
truth.  Not content,  Ike the generality of reformers,
with barely pointing out the road they ought to pur-
sue, this  able pioneer proceeded a conliderable diftance
in it, and cleared the way to  many of the greateft dif-
coveries of  his fucceffors.  But either from that love
of unintelligible fyftems which is  fo common  in igno-
rant men, or, from a dread of entering on a new road,
the termination of which they could not perceive,  it
was fome time before mankind could be drawn fiom
the beaten track.

   About this time Glauber, a German, rendered effen-
tial fervice to chemiftry, by examining the refidues of
operations which had heretofore  been thrown a fide as
ufelefs and  diftinguifhed by the names  of caput mor-
tuum, or, terra damnata.  By this he difcovered the
fulphat of foda, called  after  him Glauber's fairs, the 
(  «   )
 fUlphat of ammoniac ;  and threw great  light on  the
 proceffes for preparing the mineral acids.

    At the commencement of the feventeenth century
 the alchemical mania  arrived at its  acme.  In Ger-
 many a,fociety was formed under the name of the Ro-
 ficrueians,of which little more is known than that they
 pretended to be in poffeflion of the fecrets  of tranfmu-
, Nation, of the univerfal fcience and medicine, with the
 fcience of occult things.   In France, England, Spain,
 and moft of the other nations of Europe, the belief in
 alchemy was carried fo far that decrees were iffued by
 government forbidding it to  be  pradifed, left the va-
 lue of the current coin of the nation fhould be deftroy-
 ed, or individuals pradifing it be rendered too pow-
 erful.

    This triumph of error over reafon, like  every other
 triumph of the fame nature, was, however, doomed to    -{
 have an end.  Father Kircher,  a Jefuit,  author  of a    v
 great work entitled " Mundus Subterraneus" and Cor-
 rin^ius, a learned phyfician, commenced an attack on
 it, which, by the aid of the philofophical chemifts who    .
 made their appearance fome years after,  totally  de-
 ftroyed this chemical  monfter.

    Chemiftry had hitherto confifted of a multitude of
 fads, diffeminated  without any regard  to arrange-
 ment over many loofe  differtations on  its various
 objeds.   " As yet,"  as  Macquer  obferves, 4l there
 *■' were many branches of chemiftry  in being, though
 11 the fcience  itfelf was not yet  in  exiftence."   To- 
I  *3   )
  wards  the middle of the feventeenth century James
  Barnet, phyfician to the king of Poland,  firft collect-
  ed and arranged the principal known fads in a me-
 j thodical manner, and added obfervations  thereon.
  Bohnius, profeffor at Leipfic, likewife formed a metho-
  dical colledion. But Joachim Becher of Spires wrote
  a work entitled " Phyfica Subterranea? which from the
  precifion with which the fads are related, and his ob-
  fervations  on them,  fo  far  eclipfed the writings of
  Barnet and  Bohnius that-their works are  now  totally
  negleded,  and their names  almoft forgotten.  This
  \york, in which there are a number of cOnjedurc ve-
  rified by  iate discoveries, had  the honour of having
  for a 'commentator oner of the brighteft ornaments clie-
  miftFy. Can hoaft—I mean the celebrated Stahl.

     George Erneft S*ahl wSs born at  Onold in Franco-
  nizu, in 1660,, .-Fiort       lieft youth he appears ••'.
  have been attached to tue ttu .> of chemiftry.   But iu
• a particular manner hi*  and was direded to afceftiftr
  the true principle of in.'- ?n  natality.

     Until the time of Becfeer; the moft vr^ue notions
  were entertained on thisfubjed, the chemifts luppo-"V
  ling it to be z fulphur pervadingall in: numaLie bodies.
  Becher, perceiving that fulphur did not exift in many
  animal and  vegitable  fubftances, although inflamma-
  ble, afferted that it was not the principle of inflamma-
  bility,  but  that this  principle refided in a fubftance
  common to  fulphur as well as all other inflammable
  bodies; this fubftance  he fuppofed to be of a dry na- 
C  24   )
 ture,  and therefore called it an earthy  and to diftin-
 guifh  it  from all  other earths,  he called  it phlo-
 giston. This dodrine was adopted by Stah., who fo Tar
 Improved and extended it, that  he  is  now generally
 confidered as its founder.

   The human mind celights in t ^eculative reafoning.
 It can  fcarct'v receive  two  connected fact;  without
 wifhing to draw a general conclufion   Ir  is  lna fpirit
 of  ::t  eralization, which has given birth to fome of
 ?Le moft fublime as ^ff^%l ^e'^i^^L^eori es.  With-
out it  tJjg^nJPw^t..  i would tyi .i^TO^better than
 \v$»2---j■ ?ot> cf kilo.   Inil  d t*.   .
frfcrfa M  ■  throughout the  w   le «ijf£
           d  harmony,  it w#uld be ^
           ough all  the  materials for
    pi* are contained, yet '4'*ve »r

   ged a Hate tint th*^
The ztt'eil'Jof mankit ^
the wildefl theories ;  a
be,"rEtve tb: purpofe*r $
merit to all tb£ :  |bwn^
'' cht)r elegant.
      'ained to
      ty may
        yrange-
        t, how-
      be afiaid
ever bad, is better than nf ne   Nor
^.hat any falT?. theory, horisevei Tpecious it^rnay appear,
  ";1 bt pc  narient; for,  whatever,  system is not
«\7JNDSD IN *. - U-TH iMUST FALL L
                      J
   As fo<?n then as Becher's dodrine of ^hlogifton,  as
improved by Stahl,  became generally xnown,  it was
adopted  by  the  undiffenting voice of  the  chemical
world.  It anfwerea for the limited  ftate of  chemical
knowledge,  and the philosophers from his time until 
                     C  aa   )
within a few  years paft knew of no phenomena in
combuftion that they  could not account for fatisfado"*
rily, to themfelves,  by  this theory;

   About this time lived Mayow* an Englifh phyfician,
famous for a number of ingenious co>ije£lures. Accord-
ing :.o Dr.  Haller,  he fuppofed that nih  floating in
the air -..-as abforbed  aito the lungs an^  formed the
animal joint s,  die  heat  of the fyftem, and imparted
colour to the blood*   Blumenbach fays he was one of
the firft authors vMfr'&'flbie co&«sujw\.,*-iie taiUtio. s airs
pfpe^I-U'/Ht ■ • yM V feci d&thf.gfffuated't •') or ox '^ene,
         a****     ' ritv 'qfMayow. The .      hich
      kis Kh'i      ar 1 c .jns on this fibjedl       ^fe'
      rf^i.is <*y  uc rejpjratione, et de racbiti ?/
        pxfo»i in 166^  >U was but 34 years of;  .
when ne diev     '*'    ^J ■                    *

   We  ■:!;■"          •*' 5, ii £rhe ta.i ,t   .lltlant era
that b   ever  occurred itimffis fcienct.   Hitherto
the p. .grefs of chemiftry rw?i)een flow  nd uiicl cain*
It depend ^on accidentalrofeoverteOaiade in fearch
of chimei ivf5l objeds.   Its votaries were not led on[fo
much by the love^of truth as the love of lifc and wealt1
But the theory of Becher and Stahlf ga*  a new d;  **■
tion to the purfuits of cfcemjftsi land : mlcad or the   hi*
lofopher's  ftone, alcaheft and pWiaceai the'i  labours
were now direded to the eftabliihuieat of a theory of
combuftiou

   Stahl, whofe iriind was entirely occupied with de-
monstrating his favourite theory, and obferving all thp
                           D
 
(  26  )
  fuppofed modifications of phlogiftqn, feems  to have
  overlooked the influence of air in all the phaenomena
  which he attributes to his inflammable principle. The
  neceffuy of attending to this fluid in the operations of
  chemiftrv  had already been -demonftrated by  Boyle
  and Hales.   Tl:? difference between chemical  events
  that happen in like circumftances in air  and vscuo
  had been obferved by the former, and the latter Had
  procured from various fubftances different  kin l"  of
  air.   He  ihought air was the cauk of folidity  : i
  bodies.

    Dr. Prieftley, in purfiiipg the r ^e'.^idnts.of Ilalss,;
  difcovered many eiaftic fluids w'^eb. had  her^fore
  been er-tirely overlooked by \& chent^b.  D§. lhTe$.
 had obtained air from, >**%ium but he bad not invefti-
 gated its properr-s.   On the firft of  juguft 1774, a
 day which will ever be corifpicuous  in ' * annals of
 fcience, Priefly obtained this air*, and found it much
 purer than  atmofpheric air.   In  the courfe ©f fome
 evpcriffienrs he inftituted ^1 this air, he found it to be
 the caufe of the red colour acquired by the blood in
 paffing through the lurigs.  This difcovery rns laid the
 foundation of a, theory of animal heat that  has thrown
 more light/ot ^fi fcience of phyfiology than  perhaps
,ariy otheji di.  every ei'er made.f

  *' CLHed by him dep^IogiJHcated air,from h $ .'nppofmg it to be
air deprived of all phlogiiton, and by the Frenc. chemifts exigent
from its being the principle of acidifi.atkn.
t See note on combuftion. 
(  *7   )
  Mr. Lavoifier foon after proved that the weight ac-
quired by heated bodies is owiug to an abforption of
oxigene.*  To this difcovery we are indebted for the
French fyfterh of chemiftry.

  Before entering on this revolution, the greateft per-
haps that has ever occurred in this or any other fcience,
you will pardon me for occupying a few minutes of
your time in paying the debt  of gratitude we owe to
him by whom it was effeded.

  Lavoifier was born  at Paris,  Auguft 16th,  1743.
From his earlieft youth he manifefted a genius of no
common order. At the age of three and twenty he ob-
tained from the Academy of Sciences a gold medal for
a differtation on the beft mode of enlightening during
the night the ftreets of a great city.  Two years after-
wards he was made a member of that juftly celebrated
fociety.  As yet his mind was confined to no particu-
lar branch of fcience, but each in its turn was benefited
by his attention.   Until at  length, about  1770, La-
 voifier, ftruck with  the importance of the difcoveries
 which had recently been made by Prieftley, Black,f
 Cavendifli  and Macbride, relative to elaftic  fluids,
 turned his  attention to this inexauftable fource of dif-
 covery.  He had now entered on a  career which was
 to  rank his  name  with  thofe of Bacon, Newton  and
                     * See note B.
  t  In *755 Dr. Black d\(comei fixed air or the  carbonic acid in
calcareous earth.  He affirmed that the diflipation of  thfc air con.
 reru it into lime, and that by reftoring it again to the lime, cvlca.
 retus earth is regenerated. 
(  *8   )
Hartley.  Hi* time and fortune were devoted to fur-
thering difcoveries in chemiftry, and his houfe became
a great laboratory filled with every fpecies of appara-
tus neceffary in this fcience.   Here he made welcome
men of fcience to whatever nation they might belong,
or to whatever opinions they might be attached. Twice
a week he held affemblies at his houfe, to which  was
invited every perfon moft eminent in geometrical or
phyfical knowledge.  Here all  the  new chemical opi-
nions which appeared in Europe were difcuffed and
tefted by experiment.  Before  this  affembly Lavoifier
tried all his experiments,  and liftened with candour to
the difcuflion of them.  To this line of proceeding we
are indebted for that accuracy of experimenting, which
has been introduced, inftead of the former inqorre.d
mode.   After his experiments  and  theories had paffed
this ftrict ordeal,  and not before, he gave them to the
world.

   It is to thefe afifembties we are indebted for the new
nomenclature, which the French cheraifts have intro-
duced into this fcience.  This nomenclature has tend-
ed confiderably, by banifhing  much  of the technical
jargon of chemiftry, to its promotion, and leaves no-
thing for us to wifli, but  that they who made fo happy
a commencement had extended it  ftill farther.  We
may confider it as a happy omen of what we are to ex-
ped from an introduction of a philofophical language
into the fciences.*
»...
• See note C. 
{  *9  J
  The effects of thefe 1 .Uuirs of Lavoifier are to be
found in forty memoirs, replete with the grandeft ideas
relative to the various phenomena of chemiftry, pub-
liflied  by him,  horn  the  year  1772 to 1793,  in the
tranfadions  of the French academy.  In  1784 he
formed an idea of colleding into a lingle work all the
difcoveries he had given to the world at different pe-
riods.  This work, which  did not appear till  17&9,
exhibited the fimplicity of  his fyftem in fo forcible a
point of view that it foon gained the almoft univerfal
fuffrage of the chemical world.

  Hitherto we have beheld Lavoifier only as the phi-
fopher, rending the veil of nature, and drawing into
view all her native charms.   Let us now view him in
the nolefs exalted ftation  of private life.   If as  philo-
fopher he raifes our aftonifhment by the brilliancy of
his  difcoveries and profundity of his reafonings ;  as a
man he no lefs excites our admiration by his Arid per-
formance of all the duties of a friend, a relative, and a
citizen.   In  fhort, Lavoifier was one of  thofe truly
exalted charaders that  prove the folly of the obferva-
tion,  made by  malicious ignorance, that a  love of  fci-
ence  and a performance of the duties of life are in-
compatible.

   Cur picture has as yet difplayed none but the moft
pleafing colouring—Would to heaven ! I  could, con-
fiftently with my duty put it out  of ray hands unfi-
nifhed as it  is.   But there  is one dark (hade, which to
complete it, muft be laid in, and which will efface the
pleafure arifing from a contemplation of its beauti'; >. 
(  3*  )
   Lavoifier was ftrongly attached  to the ctufe of ici-
 inci and truth, and confequently to that of libutt.
 When the French revolution burft forth* on the afto-
 nifhed world, he, therefore, early appeared as its ad-
 vocate.  Until at length Robefpierre, having defended
 from the elevated ftation of a  Representative of the
 People, to the debafed one of their Tyrant, perceiving j
 that a love of  fcience and truth naturally produced a
 love of liberty,  determined on the deftru<5lk>n of all
 thofe who united thefe dangerous qualities.  Lavoifier
 was one  among the many marked out for deftrudion.
 No other  excufe could  be found for his execution,
 than  that he  had been a farmer-geweral under the old
 government:  But this excufe weak as it was,  was fuf-
 ficient for the tyrant, who bad the power and the will to
 deftroy him.   Let  us draw a veil  over the fatal cataf-
 trophe that lias deprived  the republic of fcience of its
 brighteft ornament.*  And while we meurn the lofs
 of this benefactor of  mankind, let us not lofe  fight of
 the pleafing hope that he  and his murderer (hall be re-
 membered as they  deferve.  Yes.' let us cherifh the
 pleafing  idea, that while the name of Robefpierre fhall
 be remembered  with deferved deteftation along with I
 thofe of Nero and Caligula to excite indignation againft
 tyranny  and its fupporters, that of Lavoifier (hall ex-
 * When the order for  his execution Wis prefented to Lavoifier he
requeued a few days to complete a courfe of experiments he had
commenced, but this was refufed and he was hurried  off to the
fcaffotd.  What may we not have loft 1 
I  31   )
cite in the breaft of every votary of fcience the warm-
•eft gratitude !
    FROM the time of Stahl  to that  of Lavoifier the
 metals were fuppofed to be compound bodies, formed
 by the union of phlogifton with peculiar earthy bafes.
 During their combuftion or calcination they were fup-
 pofed to part wTith this phlogifton to the furrounding
 bodies.  Even the weight they acquired by this fup-
 pofed lofs of one  of their conftituent principles  did
 not for a long time fhake the belief of the followers of
 Stahl in their favourite theory.  They all feemed eager
 to difcover fome opiate by which they might lull their
 reafon to fleep.   The celebrated Boyle affirmed that
 the increafe of weight in calcined metals is  owing to
 the combination  of the matter  of fire.   Boerhaave
-attributed  it to the furrounding bodies  which  de-
 pofite themfelves  upon the metal:   While  the  ge-
 nerality  of the followers of  the doctrine of  phks
■gifton fuppoled it to be the principle of levity.  Such
are the powerful  effedls produced by  the union of a
great name with any theory whatever ; like the head of
a monarch ftaraped upon bafe  metal, it ferves to give
 it currency for a time among the unobferving part of
mankind.

   At length Lavoifier proved that the increafed weight
of the calx is owing to the abforption of oxigene, and
that it is in the exact proportion of the quantity of this
gas abforbed.  He now undertook to reverfe the the»- 
C  32   )
ry of Becher and Stahl.  Inftead of fuppofing that in
combuftion phlogifton is feparated from the combulti-
ble body, he accounted for this  phaenomenon by the
body abforbing oxigene from the atmofphere, which
he difcovered confifted nearly of twenty-eight parts of
oxigene united to feventy-two of nitrogene*

   The fupporters of the doclrine of phlogifton, think-
ing it in vain to attempt any longer to uphold a fyftem
founded on the exiftence of fo chimerical a fubftance
as they had heretofore defcribed, and perceiving that
in many cafes  of the  folution of metals  in acids in-
flammable air is generated, declared this hydrogenous
gas to  be phlogifton  in an  uncombined ftate.   No
fooner  had they given to this

          --------------------u airy nothing
          *« A local habitation and a name,"

than they doomed it to deftruction.  While it retained
its Protean powers of at one time being the principle
of levity, and at another poffefling gravity, it was im-
poffible to grafp it firmly enough to deftroy it; but it
now became a fair object of difcuflion.

  The French chemifts were for  fome time at a lofs to
account for this difengagemeut of hydrogene.    At
length Mr. Cavendifh difcovered that water is a com-
pound body, formed by the union of the bafis of hy-
drogene and oxigene.  The fource from whence the
inflammable air arifes how evidently appeared not to
be, as their opponents fuppofed, from the metal dur-
ing folution parting with its phlogifton, but from the 
                     k  33   )
v.-ater combined with the acid being decompofed, its"
oxigene  uniting to the metal vvhilft its hydrogene  is
fet at liberty.

   Lavoifier  has applied his theory of the calcina-
tion of metals to the phenomena of every other f.»e-
cies of combuftion with fo happy  an effect thut  tl:s
doctrine of phlogifton has become almoft  uni\ erfally
exploded.*  That theory, which but a few years fined
commanded the undiffenting  Voice  of  the  chemical
"world, is now almoft totally forfaken. Still however the
tottering dome of this once mighty fabric is fupported
by one iblitary pillar, fo well conftructed, as by its fingle
 force to uphold it againft the warring elements, nor can
 it ever fall till this pillar is removed—Never can th,>
 doctrine of  phlogifton be faid to be totally dcilroy.,I,
 until it  (hall ceafe to rank among  its fupporters thj
 name of Priestley !

   I fhall now prefent you with the la ft and moft pleaf-
 ing revolution that has occurred in chemiftry.   Hi-
 therto  we have beheld this  fcience entirely in the
 hands of men ; we are now about to behold women af-
 fert their  juft,  though too long ncghcted claims,-of
 being  participators in the  pleafures  arifing  from a
 knowledge of chemiftry.  Already have Madam Dacier
 and Mrs.  Macauly eftabliihed their rights to criticifm
 and hiftory.   Mrs. Fulhame  has now laid fuch bold
 claims to chemiftry that we can no longer deny the fex

                   * SleNoteD.
F 
(  34   ;
 rhe privilege of participating  in this fcience alfo*.
 What may we not expect from fuch an acceffion of ta-
 lents? How fwiftly will the horizon of knowledge recede
 before our united labours? And what unbounded plea-
 fure may we not anticipate  in treading  the paths of
 fcience with fuch companions?^

   I (hall now, gentlemen, conclude with a few obfer-
 vations on the utility of  a general diffufion of chemi-
 cal knowledge throughout America.

   Living as  we do in a new,  extenfive and unexplor-
 ed country, feparated by  an immenfe ocean from all
 other  civilized nations, we mull feel ourfelves deeply
 intereftad  i n a knowledge of its mineral productions,
 l.ii 1 this can  only be arrived at through the medium of
 chemiftry.   As far as our very limited knowledge has
 yet gone, we have every reafon to believe that nature
 has been far from beftowing her  bleffings on it with a
 parfimonious hand.  Abounding as it does with the
 richeft ores of the moft valuable  metals,  we fhould be
 committing  a crime of  the  blackeft dye, were  we
 through wilful ignorance  to  trample  under our feet
 thefe invaluable  gifts of the creator.

   The only  true bafis on which the independence of
 our country can left are ac-Ricultcre 2nd manufac-
  * Mis. Fulhame hasta-e'y w;itten an ingenious piece entitled " A 4
" Efl" y on Combuft-lon, with a view ti a new an oi dying anJpainting,
" wherein the phlogiftic and anti-ph'ogiftic hjpothe.es are proved erro-
" neous-" Since the delivery of this oi ation fhe has been elected a cor-
 rtfponding niemb r of this fouety.
t See note E* 
(  35   )
tures.  To the promotion of thefe, nothing tends in a
higher degree than  chemiftry.   It  is this  fcience
which teaches man how to correct the bad qualities of
the land he cultivates by a proper  application of the
various  fpecies of manure, and  it is by means of a
knowledge of this fcience that he is enabled topurfue
the metals through all the various forms they put  on
in the earth,  feparate them  from fubftances which
render them ufelefs,  and at length  manufacture them
into the various forms for ufe and ornament in which
we fee  them.  If fuch are  the  effects of chemiftry,
how much fhould the with for its promotion be excited
in the breaft of every American !   It is to a general
diffufion  of a knowledge of this  fcience,  next to the
vit-TUE of our countrymen, that we are  to look for the
firm eftabliihment  of our independence.  And may
your endeavours, gentlemen, in this caufe, entitle you
to the gratitude of your fellow-citizens. 
N     O     T    E     S,
                         Npri; A—p. i j.


        JL  HE origin of alchemy cannot be traced farther back  with
 flny certainty than the fecond or third  century of the chriftian era.   In
 ajl probability it owed its birth to the general adoption of the proportion
 that " All  bodies  are but different  r.i.dif cations of the fume pri-
 " mitlve  matter"..,the philofophers  fuppofing  that this modification
 might be changed at pleafure by means  of certain chemical agents.

                         Note B—p. 27.
   " Rey, in the lafkcentury, afcribed  the increafed weight of metallic
 " fubftances when they ar  faid to have loft their phlogifton, to us true
 " caufe, the abforption of air, but on fuch weak grounds that he is as little
 " entitled to the honour of a  difcoverer, as a fuccefsful dreamer is to
 " that of a prophet;  nor can 1 with juftice afcribe  this honour to Dr.
 " Males,  though he extracted  air from minium; as he imputed the  in-
 " creafe of weight not only to the air, but alio to fulphur which he  ima-
 ," ginrd is abforbed fvom the fire."
                                         Kirivan en Fblcpf.cn.

                         Note C—p. 2S.
  The almoft innumerable technical terms which had been introduced in-
 fo chemiftry, before the formation of the new nomenclature,  had for a
 long tinne been a caufe of general complaint among chemifts.   The fame
 fubftance had often eight or ten different names applied to  it, mofi of
which either conveyed no idea of its properties, or wh::t is  ftill worfc,
indicated  very oppofite  ones to thofe  it poffeffed.   Within  the  little
time that elapfed from Dr. Black's difcovery of carbonic acid  it had been
knownbv the names of Fixed -.': ; Serial Acid, Meph'itic Acid,  Crc-
tjcjcu; Acid, b?c. ; but the  terms Oil  cf Tartar by the  Be!!, Gil
 ■f Vitriol,  B:ttfcr cf Antivn<~\, Cutter  r.f  Arfnis, F.'ci-j: rs  cf
 >!it:cy C;?.:. asi.ppl:-- to thsfe L-vcrai competition:, "re ftill wcrfe, asrl.ey 
                           NOTES.                        3;

 fcrve not only to burden our memories with a ufelefs quantity of words,
 but to give us  a falfe idea of the nature of the fubftances they are put for;
 as there does  not exift in the mineral kingdom, properly fpeaking, either
 ■Butter, ^/.7, or Flowers.   A reform in the chemical nomenclature be-
 came therefore  abfolutely neceffary to the promotion of fcience, or ra.
 ther it became neceffary, where  ib much error exifted, to pull down the
 old fyftem and ere£l a new one.

   In 1782 M.de Morveau propofeda reformation of the nomenclature,
 and in 178-,  M. Lavoifur, by the  affiftance of many of the beft che.
 rnifts of France, produced the following excellent plan, which is now ge-
 nerally adopted.

   1.  All thofe  fubftances which cannot be feparated into two or more
 different principles,  by any known procefs,  although they may be com-
 pound bodies,  yet are to be confidered,  until an analyfis can be made,
 as elementary,  and names  given   to them indicating their principal
 properties: thus the bafts of vital or  pure air is called oxigene from the
 Greek words oxus, acid, anJ geinomai,! beget, as byaunion of this
 fubftance  with certain bafes a'l the  acids are formed ; and the bafis of
 inflammable air is called  hydrcgene  from the Greek words udor,
 ".vuter, and geinomai, I brget,  as it is .by a union of this fubftance
 with oxigene that water is formed.

  2. When two fimple fubftances are united, the name of the compound
 is to be  fo formed, by a general rule, as at once to convey the  ideas
 of its conftituent principles.

  Thus  all  the  combinations of thofe metals with  oxigene, which do
 not  by fuch an union  form  scids, are called by the  general  names of
 oxides, as  in  the cafe of the union  of oxigene  with  lead forming red.
 lead; which, according to the new nomenclature, is called oxide cflecd.

  According to the r.c v. theory the acids  are all formed by the union
 of oxigene with  certain bafes, the names of the acids are therefore all
made by <*Wm" to the  names of their bafes, where they are known, or
when their bafes are net known to the name of the fource from whence
thev are  derived, the general termination ic.   Thus that £cid forrred
by the union of oxigene and fulphur is called tUzfutpburic ccid, ar.d the
acid procured  from the. Fluor  S;>ar. the bafis of which i. unknot, is
called the *lun ic .-.rid:   But there are acids the bafes of which are not 
;#                         NOTES.
                                                             >
 fafly faturated with oxigene, thefe are diftinguifhed' by the termination
 »us, thus when falpbur is not quite faturated with oxigene it is called
 Xhtfulpbureous acid.

   3. The neutral falts are all formed by the union of the different acids
 with alkaline, earthy or metallic bafes.  Their names are made by a.
 union of the names of the acids of which they are compofed terminating
 with at  when they are perfect acid3,  or fully faturated with oxigene,
 andrfg-when they are  imperfect^' nd the names oftlrtrbafesto which they
 are united.  Thus Glauber's fait-, which are  formed by the union of the
 Jhlpbur.cacid and fad 1 a-,- called fulpbat  of fod\, and a combination
 of the fulpbureous ac'ul and i:<-n, is calledy^/^iife  of iron.

   In favour of this  theory of a nomenclature, little  need be faid, as it
 bears internal evidence of its utility. Of the immenfe quantity of techni-
 cal words which are  laved by it I fhall give the fingle inftance of the
 neutral falts.

   There are at prefent  30  acids known, capable  of forming neutral
 falts by their union, with three alkalies, eight earths, and fourteen metals,
 in all 25 bafes, which would make 750 different neutral falts.  If to
 thefe we add thofe which could be formed  by many  of  thefe acid in a
 ftate not fully faturated with oxigene, we  fhall have not far Ihort of
 1,000  different neutral   falts.   Allowing the former  arbitrary mode
 ef naming them to prevail, there can be no doubt that each  of thefe
 falts on an average would have in the couvfe of time at leaft two names,
 we  fhould then have 2,002 names for them.   But happily  for the
 caufe of fcience our memories are faved from  being oppreffed by  this
 immenfe mafs of technical rubbifh by the proper application of the
 third rule.

   For a full account  of this nomenclature fee the memoirs of MeflYs.
 Lavoifier, De Morveau, Bertholet, De Fourcroy, Haffenfratz, and Adet;
 firft publifhed in the  tranfa&ions of the academy of Science in Paris, in
 1787, and fince tranflated into  Englifh and publifhed by Mr. St. John.

   Query. Might not the nomenclature be  extended to all combinati-
 ons of two  fimple earths by  ufing the name of  the earth found in the
 greateft quantity as   a fu'ojlanlivc,  and that of the  one found in the
 lead quantity  as an adjective.   Thus a ftone  fountd by the union of a. 
NOTES.                        39
fmaller quantity of fdex united to a greater quantity of alumiM would
be called  a fpkivus alumine, whereas  if xhtfilex  predominated it
would be..ati aluminous fdex.  Jh^might perhaps, be alfo applied to the
union of a fimple ea. th with a neutral fait, as in marble, which is  com-
pofed.of alumine and carbonate  of lime, which would then be cal!ed
alummous carbonate of lime?

               ^-      Note D.—p. 33.
   Lavoifier inftead cf fuppofing with the difciplesof Becker and St?..'.
that all inflammable bodies poffefs a certain principle,1' which they call-
ed phldgifoii, the giving out of which caufes all the various phcenomena
of combuftion, fays that they  entirely arife from the  deconipofition of
oxigindus gas, which is a compound body formed by  the union  of  a
certain bafis with the matter of heat and light,—the bafis uniting to the
inflammable body  while it;, caloric or matter of teat, and light are  fet at
liberty.  This, theory they found upon the following principles.

    r. Combuftion  is never known to take place without the piefence of
oxigene.

   2. In every known combuftion there is an abforption of oxigene.

   3. There is an  augmentation of weight in the produ^s of oanbuftioa
equal to the weight of the oxigene abforbed.

   4. In all combuftion there is adifengagement of light and heat.

   I fhall here take the liberty of fuggefting the following queries.

   Query i. Should we not confider combuftion as  an effeft of the
rleflive attraction between the bafis of the gas and the combuftible body
being ftronger than that between the fame bafis and caloric ?

   Query 2.  If to, would not the fame phcenomena take place were we
 to heat a bodkin any other gas whofe bafis has a ftronger elective attrac-
 tion to the body  than to cal»ric and light,  as do when fuch bodies are
 heated in oxigene?

    Query 3. In the combuftion of hydrogene with oxigene do we not
 find this to take place ?  Does not the bafis' of the hydrogenous gas,
 which was retained in a gafeous ftate by its union with caloric and light, 
40                            I*  O  T  E 5.      '. u
     ■.                                         '   **
 unite witb the bafis of the oxiginous gas,  and form water, ««:iv. af'4..
 £me time part with  its matter or heat and light ?^«^

    OurJtY 4. Should we  conclude becaufo thofe fubftances rA.  &*>.'
 the readjeft in oxigene will iio>bui nin any other gas, that  n|P*> ■♦-«•?£ .
 are to btfcfonnd that will?  Ought we not on the contrary to fttLt.H  ' ib"
 fbnees among, thofe which do not burn at all, or jjery flowlyln^!/  gait..;
 as the probability is that tb*f-me, fubftance. which hasgvery llm&g e!cc'
 tive attraction to the  bafis of-one gas,  w.il have but a flight one v^l: \- of
 every <«>the: ?
.•1
""*#
   Respiration may be con fide red as a  flow fpeci< s of coi> ^tfoiw
The oxigene of the atmofpheric air inhaled  is decor■..■i.'ej.  ■ '..•--b>i»|
unites  to th>-blood,  through the c-.atings  of the  Lbod veifel  ;;  ihe
lungs,  and gives it a.red colour, w  le its matter of heat is fet at l-'rrrt/
and forms the animal heat  of the fyftem.

                        Note E.—p. 34.
  The following  fhort extract lets.chemiftry, as  a proper ftud;- f vfe. ,
males,  in fo forcible and juft a point of  view that I cannot refra   $r.u «^
the pleafure of inftfrting i;.                    -                . t"

  " Chemiftry is a fcience particularly fuited te women, fuited to tbei"'  '
" talents and their §tuatk>u ; chemiftifi  is  not  a fcience of parade', it  i
'• affords occupation ^ ', infinite variety ; it demands no bodily  ffrengui.
" it can be purfhed in retirement; it applies  immediately to ufefiu*vna'
" domeftic  purpofes; and'whilft the ingenuity  of, the  moft in   jrr^*,/
" mind may bz exercifed. thare is  no danger of inflaming tlie i:   h'mC'
" t;<-..] ; the judgment is improved,  the mind is  intent  upon v    >-:..
" t  c knowledge that is acquired is exact, and the pleafure of tb£ p-y. '\. \
il is a fuivjtftnt rewarJ for the labour.
                                  rl\ettcrs for  literary  led it
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II Fv -j. N D.                         /
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