THE 
VALUE OF CHEMISTRY 
TO THE 
MEDICAL PRACTITIONER. 
A DISSERTATION TO WHICH WAS AWARDED 
THE BOYLSTON PEIZL JUNE 5th, 1873. 
BY WM. C. DABNEY, M. D. 
CHARLOTTESVILLE : 
CHRONICLE STEAM BOOK AND JOB PRINTING HOUSE. 
1873. IPIR.IEIF.^aiK!. 
The Boylston Prize Committee proposed two questions 
for the year 1873. One on “Electro Therapeutics,” and the 
other on “ The Value of Chemistry to the Medical Practi- 
tioner.” 
The following essay is an answer to the second of these 
(piestions; and it is now published by the author for distri- 
bution among his friends, with the hope that they may find 
here, in a condensed form, some information which they 
could not otherwise obtain, except by an amount of reading 
and study for which but few physicians in active practice 
have the time. 
“ By an order adopted in 1820 the secretary (of the 
Boylston Prize Committee) was directed to pul dish annually 
the following votes : 
“ 1st. That the Board do not not consider themselves as approving the 
doctrines contained in any of the dissertations to which premiums may be 
adjudged. 
“2d. That in case of publication of a successful dissertation the author 
to consider as bound to print the above vote in connection therewith.’’ |)tc |)atuo of to the j|cclii;nt |)ractifioncr. 
That a knowledge of chemistry is of essential service to 
the medical practitioner will scarcely he denied at the present 
day. So far as we are informed, Mr. Samuel Wilks is the 
only physician of any eminence who does not believe in a 
Rational system of therapeutics. 
(Lancet, January 18th, 1871.) 
In the present state of pathology we cannot say that all 
diseases are owing to chemical changes in the solids or fluids 
of the organism; nor are we in a position to affirm that all 
medicines act chemically in the relief or cure of disease. 
Many diseases, however, are certainly owing to chemical 
changes, and in those diseases medicines are generally given 
which are expected to act chemically for their relief. 
It frequently happens that there are various morbid con- 
ditions at the same time in the same individual, some of which 
seem to be owing to chemical changes, while others, so far as 
we know at present, have no direct connection with such 
changes. 
In treating of such morbid conditions in the ensuimr 
pages, we shall only speak of those which chemistry teaches 
us, or for the relief or cure of which chemical means are 
used. Some of the chemical theories of disease have been 
shown by experiment and clinical experience to be correct; 
others are as yet only suppositions. We shall endeavor, so' 
far as it is possible, to draw a line between those which have 
and those which have not been proven. 
A general statement of the different uses of chemistry to 6 
Value of Chemistry to the Medical Practitioner. 
the medical practitioner will enable ns afterwards to prose- 
cute our studies to better advantage. 
I have attempted, under the following six headings, to 
state these uses generally. 
Chemistry is of use to the medical practitioner— 
1. In teaching him the chemical composition of the dif- 
ferent solids and fluids of the organism, and the various 
chemical changes which take place in the body in health. 
2. In teaching him the chemical changes which take 
place in disease, and in furnishing him with the means of 
detecting such changes. 
3. In teaching him the action of medicines in the system 
on the chemical components of the body, and the action of 
medicines on each other. 
4. In furnishing him with the means of counteracting ini- 
proper chemical changes in the system. 
5. In the detection of poisons and in teaching the manner 
of counteracting them. 
6. In teaching the composition of and detecting adultera- 
tions in articles of diet, in medicines, &c. 
It is plain that it would be inconvenient to consider our 
subject in the order that it is stated in the above general 
headings. We propose to consider—• 
1. The different fluids of the organism. 
2. The different solids of the organism. 
3. The chemical tests for the different poisons and their 
antidotes. 
4. Those substances which are chemically incompatible. 
The chemical composition and the uses of the different 
kinds of food, medicines and mineral waters will be consid- 
ered in considering the different diseased states. 
In considering both the fluids and solids we shall study— 
First, briefly, their physiological chemistry ; secondly, their 
pathological chemistry ; and, thirdly, the therapeutical in- 
dications to which their pathological chemistry gives rise, 
and the means of fulfilling them. The necessity of a correct Value of Chemistry to the Medical Practitioner. 
7 
knowledge of the physiology of an organ before we can un- 
derstand its pathology is universally admitted ; and hence 
we need make no explanation for pursuing our studies in the 
order stated above. 
The fluids of the organism are : 
Secretions.—Blood, mucus, milk, tears, sebaceous matter, 
(semi-solid), saliva, gastric juice, pancreatic juice, bile, serum 
of serous, membrane, perspiration. 
Excretions.—Brine. 
Bile may be classed under both headings (secretions and 
excretions), for the general opinion among physiologists at the 
present day is that the liver is both an excreting and secreting 
organ—excreting cholesterine and secreting sugar. 
It frequently happens that the presence of some abnormal 
ingredient in one of the fluids is accompanied by its absence 
or presence in reduced quantity in some other where it nor- 
mally belongs. For example—when urea is present in large 
quantity in the blood, it is absent or present in greatly re- 
duced quantity in the urine. 
In such cases the pathological condition will be considered 
at length under one of the fluids, and briefly considered under 
the other. 
The blood, circulating as it does through the entire body, 
carrying nourishment to the various parts of the body and 
absorbing the elfete materials, which in their turn are to be 
eliminated from it by the appropriate organs, must ne- 
cessarily be intimately associated with many of the “ ills 
which flesh is heir to.” At the present day, however, it is 
rarely examined chemically in disease. One reason for this, 
perhaps, is that bloodletting, as a remedy, is much more rarely 
resorted to now than formerly. For our knowledge of the 
chemical constitution of the blood in the different diseases 
we are chiefly indebted to Simon. Before considering the 
chemical changes in diseases, however, we should have a cor- 
nr.oon. 8 
Value of Chemistry to the Medical Practitioner. 
rect understanding of the chemical composition of the blood 
in health. 
Its physical characters are too well known to need a word 
of explanation; nor does it belong properly to the subject 
under consideration. 
Becquerel and Rodier give the following table (taken from 
Flint’s Physiology of Man, Yol. 1/p. 132), as showing the 
mean result of the analysis of the blood of twenty-two healthy 
men: 
[Becquerel and Rodier’s table showing the composition of the blood.] 
Density of the blood, - - - 1050.000 
Water, ------ 881.000 
Globulin, - 135.000 
Albumen, - - - - - 70.000 
Fibrin, - - 2.500 
Seroline, ----- 0.025 
Cholesterine, - - - - - 0.126 
Carbonate of Soda, 
Free Soda, 
Sulphate of Soda, 
Phosphate of Soda, 
Carbonate of Potash, 
Sulphate of Potash, 
Phosphate of Potash, 
Sulphate of Magnesia, 
Carbonate of soda most 
abundant, - 2.300 
Phosphate of Lime, 
Phosphate of Magnesia, 
0.350 
Iron, - 0.550 
Undetermined extractive matters, - - 2.450 
Besides the substances given in the above table and the 
gases contained in the blood, the following have been found 
to be either constant or temporary constituents: 
Sugar, in the hepatic veins. 
Fatty emulsion, in small quantity after eating. 
Coloring matter of the serum. 
Urea, in very minute quantities. 
Uric acid (as urate of sqda) in minute quantity. 
Creatine and creatinine, in small quantity. Value of Chemistry to the Medical Practitioner. 
9 
Having thus briefly considered the physiological chemistry 
of the blood, we shall proceed to study— 
1. The increase or decrease of the normal constituents of 
the blood; their clinical significance, and the therapeutical 
indications derived from them ; and 
2. The presence of foreign matters in the blood, their 
clinical significance, &c. 
1. Plethora.—An increase in the solid constituents of 
the blood, particularly the red corpuscles, constitutes plethora. 
But little is known concerning the formation of the red cor- 
puscles, and hence we can do nothing directly to lessen their 
formation. Bearing in mind their chemical composition we 
may do something by the administration of suitable diet, but 
even this is very unsatisfactory. Certain medicines, such as 
mercury, seem to have the power of lessening the number of 
red globules. The manner in which they do this is unknown. 
Mr. Odling, in his animal chemistry, pp. 146-156, (London 
edition,) advances a theory concerning the modus ojperandi of 
alteratives, which gives a possible clue to the action of 
mercury in lessening the number of red corpuscles. His 
theory is that mercury, iodine, arsenic, and other medicines 
act by virtue of their “chemical mobility,” or by their power 
of deoxidizing when there is an excess of oxygen, and oxidiz- 
ing when oxygen is wanted. This theory is certainly plausi- 
ble, but, of course, it is as yet only a theory. Every one, 
however, is familiar with the use of of mercury, 
arsenic, &c., in the laboratory, as cA-oxidizing agents, and 
the use of the j?<?r-salts of the same metals as oxidizing 
agents, and we can see no reason why these substances should 
not have the same action on the constituents of the human 
body. 
2. Anaemia.—A decrease in the number of red blood cor- 
puscles constitutes Anaemia. 
The whole volume of blood is frequently reduced by hem- 
orrhage, but the watery portion is quickly replaced by absorp- 10 
Value of Chemistry to the Medical Practitioner. 
tion. The red corpuscles have been known, however, to be- 
come as low as 70, 60, or even 21 parts per 1,000, (Flint's 
Physiology,p. 61.) 
Anaemia occurs in tuberculosis, cancer, Bright’s disease, 
hemorrhages, affections of the liver—especially cirrhosis—all 
febrile disorders, malaria, saturnine diseases as a result of the 
administration of mercury and chlorosis.—[l1 lint). 
The therapeutical indications are to furnish food rich in 
albumen and the administration of iron.—{Headland on action 
of remedies in the system, jpjp. 319-320). Let us, therefore, 
consider briefly the articles of diet which are most suitable 
from their chemical composition to restore the lost elements 
to the blood. In the first place we should bear in mind that 
all the nitrogenized alimentary principles are converted into al- 
bumen before they are applied to the nutrition of the tissues. 
The fluid form of albumen is most easily digested, then co- 
agulated albumen, then fibrin, then casein, and lastly the de- 
rivatives of albumen, gelatine, cliondrine and cartilage.—{Le- 
thehy on Food, jp. 55). Skim cheese contains by far the 
largest per cent, of nitrogenous matters (44.8 per cent.), but 
this is in the form of casein, and we have already seen that 
this is not very digestible. Lean beef contains about 19 per 
cent. Mutton a little less. The nitrogenized matters in the 
meats are, of course, in the form of fibrin. Eggs, which con- 
tain albumen in a liquid form and hence in the most digestible 
condition, contain 14 per cent. The quantity of nitrogenized 
materials in the different articles of food given above is taken 
from Letheby.—(Table 3, p. 5). Other chemists differ witli 
him slightly. Berzelius found that the flesh of the ox con- 
tained about 2.20 per cent, of albumen analogous to the white 
of egg and the serum of the blood, and Payen found about 
22.93 per cent, of nitrogenized matters in cooked beefsteak. 
The same author found 4.30 per cent, of nitrogenized matters 
in cow’s milk. Besides the large quantity of albumen con- 
tained in eggs, iron is also found in the ash after incineration. 
The vegetables containing albumen (or substances con- Value of Chemistry to the Medical Practitioner. 
11 
vcrtible into it), in most common use, are wheat, which con- 
tains from 13 to 15 per cent, of gluten ; the succulent vege- 
tables which contain vegetable albumen are peas, beans, &c., 
which contain a substance analogous to casein. 
Of course, in the selection of articles of diet for sick per- 
sons, care should be taken to choose those which, besides hav- 
ing a suitable chemical composition, are most easy of digestion. 
Iron, which, as we have seen in the table given previously, 
exists in the blood in the proportion of 0.550 per 1,000, is 
found in the hematine or coloring matter of the blood ; and 
hence when the globules are lessened in amount the quantity 
of iron is also lessened. It should, therefore, be supplied in 
some form as the food wo take does not contain it in sufficient 
quantity to supply the loss. The form or particular prepara- 
tion of iron used does not seem to be a matter of much con- 
sequence. Dr. C. D. Meigs, it is true, recommended the pure 
iron (iron by hydrogen), on chemical grounds, because he 
thought that the simple action of the acids of the stomach up- 
on the metal would require a less expenditure of force than if 
a salt of iron had to be decomposed, and then acted upon in 
such a way as to be absorbed by the stomach and intestines. 
Those who believe that the acidity of the gastric juice is 
caused by hydrochloric acid will probably think that it is 
owing to this fact that the mnriated tincture of iron seems, in 
many cases, to be preferable to the other preparations. The 
supporters of the lactic acid theory of the gastric acidity might 
argue in a similar manner, but all of the views, although more 
or less plausible, are only theories, and do not admit of proof. 
3. Fibrin-.—Fibrin is found in the blood in the proportion 
of 2.50 parts per 1,000. It coagulates outside of the body, and 
under certain circumstances in it. It is soluble in dilute solu 
tions of caustic alkalies and in phosphoric acid.—(Fowne s 
Chemistry, p. 544). The means by which fibrin was held in so- 
lution in the blood was for a long time unknown. Various liy 
pothesis were advanced, but until the year 1856 no definite con- 
clusions were reached. In that year Dr. B.W. Richardson expe- 12 
Value of Chemistry to the Medical Practitioner. 
rimented at great length upon the subject, and came to the con- 
clusion that fibrin was held in solution in the blood by am- 
monia, and that it was the loss of ammonia by evaporation 
which caused the fibrin to coagulate out of the body. These 
views were adopted by the great majority of physiologists, and 
are generally entertained at the present day. Richardson, it 
is true, has withdrawn his views on the subject of the fibrin 
of the blood being held in solution in that fluid by ammonia, 
but the fact remains that it is soluble in ammonia and the 
other alkalies. It is not necessary, however, for us to pursue 
our studies further in this direction. Certain it is that chem- 
istry lias shown that fibrin is soluble in the alkalies and their 
carbonates, and from this, much useful information may be 
drawn by the practical physician. 
Hyperinosis.—In certain diseased conditions the relative 
amount of fibrin is increased and this increase is called by 
Simon, “Hyperinosis.” According to this author the follow- 
ing arc the chief diseases in which the amount of fibrin is in- 
creased : Metro-peritonitis, carditis, bronchitis, pneumonitis, 
pleuritis, nephritis, cystitis, rheumatism, erysipelas, phthisis, 
puerperal fever and eclampsia. Of these, acute articular 
rheumatism presents the largest increase of fibrin, pneumo- 
nitis next, and capillary bronchitis next. 
Blood-letting increases the relative amount of fibrin, and 
hence the liability to the formation of a heart clot after severe 
hemorrhages. Dr. Meigs explains this subject very ably and 
fully in his “System of Obstetrics.” 
As before stated, it has been found that the alkalies intro- 
duced into the blood vessels, or mixed with blood after it is 
drawn, impede, or may arrest, the process of coagulation. 
And it has been proved that nearly all medicines (all that are 
soluble) are absorbed and gain access to the blood.—(Head- 
land, ojp : cit. p. 61, et seg). 
The practical deductions to be drawn from these facts are, 
that in all those diseased conditions, when tite amount of 
fibrin is increased, ammonia or some other alkali should be Value of Chemistry to the Medical Practitioner. 
13 
administered. The benefit of alkalies in the treatment of 
acute articular rheumatism is universally acknowledged, and 
we shall have occasion, in a future section, to study their 
modus operandi at greater length. The employment of am- 
monia in the treatment of pneumonitis is rapidly growing in 
favor with the profession. In hemorrhage from wounds, or 
injuries of any kind, when the mouth of the bleeding vessel 
is to be stopped by a coagulum, alkalies would be contra- 
indicated. I have frequently used carbonate of ammonia, 
however, in the treatment of uterine hemorrhages, both ante- 
partum and post-par turn, and I think with good effect. Of 
course, the ammonia is not given to check the hemorrhage, 
but to prevent the formation of an embolus or heart clot after- 
wards. The mouths of the bleeding vessels in uterine hem- 
orrhages arc closed by their compression between the fibres 
of the uterus and hence the formation of a coagulum is not so 
desirable. Fayrer and other surgeons in India have found 
the injection of ammonia into the veins of great service in 
cholera. Of course the immediate effect of this would be that 
of a powerful stimulant, but we are inclined to think that be- 
sides this effect the ammonia prevents the formation of a co- 
agulum in the heart or pulmonary vessels, which experience 
teaches is a common mode of death in this disease. In throm- 
bosis and embolism also, ammonia lias been used with deci- 
ded benefit. Dr. B. \V. Richardson first used ammonia in 
these cases. lie has found it very advantageous to combine 
iodide of potassium with it, as otherwise it produces too great 
a fluidity of the blood. It is probable that this will be more 
serviceable as a preventative than as a cure of embolism. 
Hypinosis.—A decrease in the amount of fibrin in the 
blood is called by Simon Hypinosis. This condition is much 
less frequent than hyperinosis. The diseases in which it oc- 
curs according to Simon are Typhoid and every form of con- 
tinued fever, varioloid, rubeola, scarlatina, intermittent fever, 
cerebral hemorrhage.—(Chemistry of Man, p. p. 235-250). 
Flint, however, says that it occurs in continued fevers provi- 14 
Value of Chemistry to the Medical Prvctitioner. 
ded they are not accompanied by acute inflammation in any 
part. In varioloid, lie says, it is above the normal standard ; in 
rubeola it is normal, in scarlatina a little decreased, and it is 
not diminished in the intermittent fevers.—(.Practice of Medi- 
cine, pp. 70-71). 
Food rich in fibrin, such as the various meats, are indi- 
cated in this diseased condition. We have seen, previously, 
the amount of nitrogenized matters in the leading articles of 
diet. The flesh of the ox is probably the richest in nitrogen- 
ized matters. 
The mineral acids have been proposed on theoretical 
grounds and have been found of service. It was thought that 
as the fibrin of the blood was kept in a fluid condition by an 
alkali, that if a portion of the alkali were neutralized by an 
acid more fibrin would accumulate. Probably a more rational 
explanation is, that by the administration of acids a larger 
amount of acid is set free in the blood, and is thus furnished 
to the gastric juice to aid in digestion.—(Headland, op : cit, 
pp. 121-122). If the latter theory be the correct one, it is 
probable that lactic acid or the acid phosphate, of lime would 
be as serviceable as the mineral acids. 
4. Albumen.—Albumen is present in the blood in the pro- 
portion of 70 parts per 1,000. All the nitrogenous substances 
which are taken in the system as food seein to be con- 
verted into albumen before they are absorbed. Fibrin, which 
plays so important a part in the animal economy, is formed 
from albumen. It may be either increased or diminished in 
quantity. Concerning its increase, but little is known. It is 
diminished in Bright’s disease of the kidneys, and in some 
other affections of the same organ ; and when it is present in 
the blood in too small quantity, it is usually present in the 
urine. The density of the blood is owing chiefly to albumen, 
and hence, when the quantity of this ingredient is diminished, 
the serum of the blood transudes and causes dropsy. This 
theory of the cause of dropsy, it is true, has been opposed by 
.Dr. 11. C. Wood, of Philadelphia, (American Journal of Value of Chemistry to tlie Medical Practitioner. 
15 
Medical Sciences, July, 1871,) but it is generally thought that 
his arguments are not sufficient to overthrow it. The quantity 
of urea and of albumen in the blood seem to bear an inverse 
proportion to each other. We shall have occasion to refer to 
this more fully hereafter. As the presence of albumen in the 
urine is a much more prominent symptom than its absence in 
the blood, the subject of albuminuria can more appropriately 
be considered under the head of urine. 
5. Fat.—Fat, as we have seen previously, exists in the blood 
after a full meal in considerable quantity. One source of the 
fat of the blood is that taken with the food as fat, but Claude 
Bernard showed that fat was produced by the liver, at the 
expense of the saccharine or amylaceous articles of food. The 
amount generated or deposited in the system may be greatly 
increased by a diet consisting largely of fatty or amylaceous 
articles and by muscular inactivity. An excess of fat in the 
heart is apt to coexist with fatty degenerations of the heart or 
other parts of the muscular system. 
The indications when it is present in abnormally large 
quantity, are to give food which contains as small a quantity 
as possible of fatty or amylaceous matter, and to make the 
patient take as active exercise as his strength will admit of. 
Nitrogenized articles of diet are suitable. A small quantity of 
fat will nearly always find its way into the system, but this 
will be burnt off in keeping up the animal heat. Corn bread 
should be avoided on account of the oil or fat which it con- 
tains. The bread used should be made of white well “bolted” 
flour. This is not nearly so fattening as corn bread. Mr. 
Thomas J. Hand, of Hew York, in a very able pamphlet on 
wheat and the process of converting it into flour, has shown 
that most of the gluten is removed with the bran in the manu- 
facture of flour. A French machinist has invented a machine 
by which this gluten, which is the most nourishing part of the 
wheat, can be retained in the flour, and thus the proportion 
of nitrogenous matter in it greatly increased. 
Lean meat should be used, particularly beef or mutton. Of 16 
Value of Chemistry to the Medical Practitioner. 
fowls only those with white meat are appropriate. The dark 
meat fowls have the fat and lean mixed together in such a 
manner that it cannot be separated. It is highly probable 
that mercury would lessen the quantity of fat in the system, 
but as far as I am aware no observations have been made on 
on this subject, and, indeed, when there was fatty degeneration 
of the heart, mercury would be contra-indicated. 
6. Glitco-haemia.—Simar is found in the blood in health 
in small quantity—in the hepatic veins and right side of the 
heart. Its function is probably to assist in the formation of 
fat and the production of animal heat. Its presence in the 
blood in abinormal quantity constitutes “ Gluco-haemia’ ’ It 
makes its appearance in the urine at the same time, and will be 
considered under that head on account of the facility with 
which it is recognized in that fluid. 
7. Uraemia.—Urea, as we have seen in the table given pre- 
viously, exists in the blood in health in very minute quantity. 
Wurtz has shown that it is present in the lymph and chyle in 
large quantity. In health urea is excreted by the kidney. 
These organs were at one time thought to produce it (Oppler). 
The experiments of Bernard, Barreswill, and Hammond, how- 
ever, have shown that it is formed in the system by the gene- 
ral process of disassimilation and taken up by the blood to be 
separated by the kidneys. 
The excess of urea in the blood gives rise to a condition 
known as Uraemia. This excess may lie owing either to ex- 
cessive formation, which occurs in Leuchaemia, or to deficient 
elimination, which occurs commonly in connection with al- 
buminuria.—(Allbut on th$ use of the Opthalmoscope, p. 
219). Nothing is known concerning the excessive formation 
of urea. It may be present in the blood from deficient elimi- 
nation when there is no albumen in the urine. The existence 
of uraemia may be inferred whenever in connection witli the 
symptoms of uraemic poisoning the secretion of urine is greatly 
diminished. The urine is also generally of low specific gravity. 
An analysis of the urine will of course enable the physician Value of Chemistry to the Medical Practitioner. 
17 
to detect tlie absence or diminution of the amount of urea with 
certainty. 
Physiological experiment and clinical experience both aho'S? 
that urea is eliminated vicariously by the bowels and the skin* 
It is converted, however, in its passage through the alimert* 
tary canal into carbonate of ammonia, and appears in the 
evacuations in that form. Uraemia is chiefly to be appre- 
hended in Bright’s disease—in scarlet fever, or rather as a 
sequel of scarlet fever, and in all cases where the circulation 
through the kidneys is in any way impeded. The uraemia, 
which occurs sometimes during pregnancy, is caused by the 
pressure of the gravid uterus on the veins in the pelvis. A 
reviewer of different works on puerperal eclampsia, &c., in 
the American Journal of the Medical Sciences for April, 1871, 
comes to the conclusion that convulsions are not caused by 
the presence of urea or of carbonate of ammonia in the blood; 
but this statement is contrary to the views entertained by the 
great mass of the profession, and can scarcely be accepted with- 
out further proof. 
Uraemia is nearly always accompanied by albuminuria. 
Bearing in mind the vicarious mode of elimination of urea, 
by the skin and bowels, remedies would seem to be indicated 
to promote the action of these organs. The practice of greas- 
ing the skin in scarlet fever is obviously not in accordance 
with scientific principles as the perspiratory function is thus 
greatly interfered with and one channel for the elimination of 
urea is cut off. Greasing was resorted to to lessen the tem- 
perature, but this can be done equally well by sponging with 
cold wrater, and in this way diaphoresis is promoted rather 
than checked. 
8. Uricaewia.—Uric acid exists in the blood in health in 
minute quantity as urate of soda. Uric acid is probably 
formed like urea, by the general process of disassimilation in 
the system, and, like urea, it is excreted in health by the kid- 
neys. Its presence in the blood in abnormal quantity gives 
rise to the condition known as uricaemia, a; d this excess has 18 
Value of Chemistry to the Medical Practitioner. 
been shown by Garrod to be the cause of gout. Like urea 
when the amount of uric acid in the blood is increased it is 
diminished in the urine. Garrod found that it was considera- 
bly diminished during a paroxysm of gout, and habitually les- 
sened in the chronic form of the disease. The concretions in 
and around the joints in gout consist chiefly of urate of soda 
which is very insoluble. The indications of treatment in gout 
are to give remedies to counteract chemically the excess of 
acid and to form some salt of uric acid more soluble than the 
urate of soda. The salts of potash were proposed by Garrod 
on theoretical grounds and have been found of very great 
service. About eight or ten years ago carbonate of lithia was 
proposed as a remedy in this affection, and according to Flint, 
Sr., lithia water, which is a solution of lithia in corbonatcd 
water, has been found a very useful remedy in New York. 
Niemeyer does not recommend alkalies, but advises the free 
use of acid drinks during the attacks. The kind of acid is not 
mentioned, but it is probably lemonade to which he alludes 
by acid drinks. If we are right in this supposition it is ex- 
tremely probable that the lemon juice acts by the conversion 
of the citrate of potash which it contains into carbonate of 
potash and the neutralization of the uric acid by this salt. Ur. 
Owen Rees thought the lemon juice acted by converting the 
uric acid into urea, which is much more soluble than uric acid. 
This explanation, however, is extremely improbable.—(For 
a very able exposition of the relation of urea to uric acid 
see Odlinf s Animal Chemistry, London edition, pp. 128- 
129). The late Dr. Buckler, of Baltimore, proposed the phos- 
phate of ammonia with the view of obtaining by double de- 
composition the phosphate of soda and the urate of ammonia, 
both of which salts are very soluble in water—(the latter, 
however, only in the presence of chloride of sodium). Ben- 
zoic acid was proposed by tire and has been used considerably 
with the view of converting the uric acid into hippuric acid, 
which is much more soluble than the uric. 
9. Cholestkkaemia.—Cholesterine is found in the blood Value of Chemistry to the Medical Practitioner. 
19 
in the proportion of 0.125 parts per 1,000. It originates in 
some manner, as yet not understood, in the brain and nervous 
system, and in health is excreted by the liver—{See article by 
Flint, Jr., in American Journal of the Medical Science, 
October, 1862). It is discharged with the faeces as stercorine ; 
if retained in the blood it gives rise to a peculiar train of 
poisonous symptoms to which the name of cliolesteraemia has 
been applied. Its excretion is interfered with in all structural 
diseases of the liver. Many cases which are thought to be 
uraemic poisoning are doubtless owing to the cholesterine 
being retained in the blood. Cliolesteraemia frequently oc- 
curs during pregnancy.—{For a very able article on this sub- 
ject, by the late Dr. It. B. Nelson, of Charlottesville, Va., 
seethe Virginia Medical Journal for November, 1867). It 
has been detected in the urine during an attack of jaundice 
by Gmelin.—{Simon loc. ciU,p. 532). Although it is a non- 
nitrogenous product, it is possible that this is the vicarious 
mode of its elimination, and measures to increase the action 
of the kidneys would be advisable. Nothing definite is 
known on the subject of the treatment of cliolesteramia. 
The mercurial preparations and podophillin have been pro- 
posed from their apparent power of promoting the action of 
the liver. 
The foreign matters most frequently found in the blood, 
and which are indicative of chemical changes occuring in the 
organism, are— 
Lactic acid, biliary matters, pus. 
10. Rheumatism.—Lactic acid is not found in the blood 
in health. The lactates are frequently taken into the stom- 
ach as food; but they are speedily converted into the carbon- 
ates before reaching the blood. Lehman proved this by ex- 
periments on his own person. The sugar which is formed 
in the liver is carried by the blood to the lungs, and is tlwm 
burnt off after being converted into lactic acid,—{Flint’s 
Dhys., \st Vol.j p> 68): It is doubtless frequently present in 
the blood in small quantity, and for a short time without giv- 20 
Value of Chen> stry to the Medical Practitioner. 
ing rise to any disturbance; but its presence in the blood in 
quantity gives rise to rheumatism. This theory of the cause 
of rheumatism was advanced by Rrout, and at the present 
day is generally adopted by physicians. An English physi- 
cian, Dr.' B. W. Eoster, has recently reported two cases 
(,British 2£ed. Journal, Dec. 23d, 1871) where lactic acid 
was given for the cure of diabetes ; and in both cases aii at- 
tack of acute articular rheumatism was brought on. The 
attacks came on when the acid was taken, and ceased when 
It was discontinued. When moderate quantities of the acid 
were tolerated, an increase in the dose brought on the painful 
inflammation of the joints. 
The indication of treatment then in acute articular rheu- 
matism, so far as the lactic acid is concerned, is the adminis- 
tration of alkalies to counteract chemically the acid in the 
blood. This is the theoretical treatment of rheumatism, and 
experience has provod it to bo the best. The carbonates of 
the' alkalies are generally used ; and of these carbonate of 
potash is perhaps the most popular. Some years ago the per • 
inanganato of potash was proposed, probably from the fact 
that the permanganic acid is feebly united with the base.— 
(.Fownes’ Chemistry, j). 277). The writer, while resident 
physician ot the Seaman’s Hospital, Baltimore, in 1868, in- 
stituted a series of experiments and observations to determine 
the value of this salt. The conclusion reached was, that it 
was uncertain and could not compare with the carbonates of 
potash and soda and .Rochelle salts as a remedy for rheuma- 
tism. We have seen previously that lactic acid is formed in 
the lungs from sugar. It is unnecessary in this connection 
for uS to consider the origin and function of sugar ; it is suf- 
ficient for us to bear in mind that it is produced in the organ- 
ism, and is also taken in with the food. It is important 
tlreroforo to givo as little sacharine food, or food easily con- 
verted into sugar, as possible. Under the head of Diabetes, 
will be given a table of the different vegetables arranged 
in order according to the proportion of starch which they, 
containj Value of Chemistry to the Medical Practitioner. 
21 
11. Biliary Matters.—Biliary matters are frequently 
present in the blood, giving a yellow coloring to the skin at 
such times. The presence of the biliary matters is sympto- 
matic of a variety of disorders of the liver and gall bladder, 
but it is a matter about which but little need be said in this 
connection. As a general rule when the biliary coloring 
matter is present in the blood it also makes its appearance in 
the urine, and we shall notice it under that heading. 
12. Byaemia.—Bus in the blood constitutes a morbid 
aflection known as pyaemia. It seems almost useless to re- 
fer to this diseased condition in an essay on the practical 
value of chemistry in medicine; but as some authorities have 
recently proposed a mode of treatment which seems to act 
chemically, I have thought it proper to notice the subject 
briefly. It is seldom necessary to test the blood chemically 
for pus. The symptoms of pyaemia are usually sufticiently 
well marked; ammonia, however, is usually given in chemi- 
cal works as a test. Blood treated with ammonia dissolves 
into a clear fluid, while pus similarly treated is coagulated. 
Hence when there is pus in the blood we And strips of stringy 
substance if the blood is treated with ammonia. The micro- 
scope has also been much used as a test for pus in the blood. 
If, however, the views of Conheim and his disciples be cor- 
rect that the pus-corpuscles are identical with the white cor- 
puscels of the blood, the microscope will be of little value in 
this connection. Virchow, who does not believe in this iden- 
tity of white blood corpuscles and pus-corpuscles, acknowl- 
edges that the only way of distinguishing them is by their 
mode of origin.—(Cellular Pathology, p. 1S8). Rindfleisch 
says that 'most, pus-eorpuscels are derived from the exudation 
of white corpuscles, “but the participation of epithelium 
cannot be excluded.”—{Pathol. Histology, p. 111). The 
chemical treatment of pyaemia, to which reference has pre- 
viously been made, consists in placing tho patient in a car- 
bolized atmosphere, and in the administration internally of the 
carbolates or feulpho-carbolates. This treatment has the high 22 
Value of Chemistry to the Medical Practitioner. 
sanction of Dr. Lionel Beale and Mr. John Wood.—{Med. 
Press and Circular, April 19t/i, 1871). Carbol has the 
power of dissolving the pus-corpuscles, and this is doubtless 
its mode of action in pyaemia. This treatment would ac- 
quire still greater importance if the views entertained by 
some histologists that the white corpuscles have the power of 
proliferating after being exuded should prove to be correct.— 
( Vulpian and Hayden, Gazette llebdomadaire, JVb. 7, 1870). 
Bill found that when much oil was present, carbol was inert, 
and that after its solution in oil it could not be detected by 
chemical tests. According to Fownes as much as one per 
cent, of cholesterine has been found in pus, and this being a 
fatty substance it is probably by combining with this that the 
carbol acts. 
GASES IN THE IiLOOD. 
Having considered the increase and decrease of the normal 
constituents of the blood, which are in a solid or fluid condi- 
tion, and having considered the abnormal ingredients which 
are occasionally present in the blood, we shall proceed to 
consider the gases which are in it. 
That oxygen is taken into the blood during inspiration, 
and carbonic acid is given off during expiration, is universally 
known. The atmosphere consists of about four-fifths nitrogen 
and one-fifth oxygen. The nitrogen and oxygen are probably 
in a state of mixture, though some chemists think they are in 
a state of feeble chemical combination. A proper supply of 
oxygen is absolutely necessary to life, and if from any cause 
it is not obtained by inspiration, the carbonic acid remains in 
the blood and causes suffocation. 
13. Asthma.—Let us now see under what circumstances, 
though the atmosphere be normal, too little oxygen is carried 
to the blood. The minute bronchial tubes are of such a size 
as to carry a certain quantity of oxygen (in the adult under 
ordinary circumstances about eighteen cubic feet per day) to 
the blood. Now if these tubes are contracted it is evident 
that a smaller quantity of air is inhaled and a smaller quan- Value of Chemistry to the Medical Practitioner. 
23 
tity of oxygen is absorbed. Now this contraction does some- 
times occur. It has been conclusively proved that in asthma 
tho minute bronchial tubes are in a state of spasmodic con- 
traction.—{Nicmeyer's Practice, Vol. ls£, jp. ). The in- 
dications of treatment, therefore, in asthma are to relieve the- 
spasm so that the normal quantity of air can enter the lungs, or 
else to furnish a gas which contains a larger quantity of avail- 
able oxygen in a given volume than atmospheric air. Both 
of these indications we think can be fulfilled by chemical 
means. Carbonic acid when retained in the blood causes re- 
laxation of the muscles, both voluntary and involuntary, an- 
aesthesia, and finally, if oxygen is not furnished in proper 
quantity, the anaesthesia gives place to asphyxia and deatli 
results. It is a well known fact that pressure on the carotid 
artery, so as to impede the circulation in the brain, causes 
retention of carbonic acid in the capillaries (where the inter- 
change of gases normally takes place) and anaesthesia is the 
result. It is plain that carbonic acid gas may be present in 
the blood in large quantity from the inhalation of this gas ; 
but, bearing in mind the fact that carbonic acid is expelled 
from the blood owing to the greater affinity of the blood cor- 
puscles for oxygen than for carbonic acid, it is plain that if 
the oxygen be absorbed, as it were, in some other way, the 
carbonic acid would remain in the blood and cause relaxation 
and insensibility. We are not aware that the inhalation of 
carbonic acid has ever been tried as a remedy for asthma. 
Dunglison says it has been used much diluted as a sedative, 
but he does not give any of its special applications. The in- 
halation of nitrous oxide gas in asthma has recently been 
strongly advocated by Dr. Holden, of Newark, N. J.— 
(.American Journal Med. Sciences, Oct., 1872). He thinks 
that its “ active principle ” is the nitrogen which it contains; 
but a much more probable explanation of its modus operandi 
is that it has a great affinity for oxygen, and acts as an absorb- 
ent for the oxygen of the air, thus allowing the carbonic 
acid to remain in the blood and produce its characteristic ef- 24 
Value of Chemistry to the Medical Practitioner. 
fects. In this way the bronchial tubes are relaxed, and a 
sufficient quantity of atmospheric air can enter the air cells. 
I have no experience with nitrous oxide myself, but my friend 
Dr. J. W. Scribner, an experienced dentist of Charlottesville, 
Va., who uses it frequently, tells me that the face and lips 
become very blue, and that the bleeding is apt to be greater 
than natural from the extraction of teeth when it is used. 
Both of these circumstances tend to prove the correctness of 
the theory advanced above. The second indication in asthma 
is to furnish a gas which contains a larger quantity of avail- 
able oxygen in a given volume than atmospheric air under 
ordinary pressure. The most direct method of fulfilling this 
indication is to administer pure oxygen gas, and this has fre- 
quently been done. Niemeyer speaks favorably of the use 
of compressed air. The two modes of treatment are obvi- 
ously incompatible, and as a general rule remedies to relieve 
the spasm are more used than those which supply oxygen in 
a concentrated form. 
MUCUS. 
Mucus is a clear colorless fluid, viscid owing to the pres- 
ence in it of a peculiar animal principle mucosine. Accord- 
ing to Nasse (Simon loc.cit.,p. 532) the composition of pul- 
monony mucus is as follows: 
Water, ...... 955.52 
Animal Matter, - 33.57 
Fat, 2.89 
Chloride of Sodium, .... 5.83 
Phosphate of Potash and Soda, - - - 1.05 
Sulphate of Potash and Soda, - - - 0.65 
Carbonates of Potash and Soda, ... 0.49 
The composition of mucus doubtless varies somewhat in 
different parts of the body. Mucosine is not soluble in water, 
but is soluble in the alkalies and their carbonates. Mucus is 
sometimes present in too great and at other times in too small 
quantity, but so far as is known its secretion is not directly 
influenced by chemical agents. In old persons, however, and Value of Chemistry to the Medical Practitioner. 
25 
in children'or in persons of any age who are much debili- 
tated, the accumulation of mucus in the bronchial tubes may 
give rise to dangerous symptoms, and may even cause suffo- 
cation. Under these circumstances, besides the use of emet- 
ics to cause the discharge of the phlegm by vomiting and the 
relaxation of the muscular fibres of the bronchial tubes, 
remedies are indicated which have the power of dissolving 
the mucosine, and thus lessening the consistency of the mu- 
cus. Even when persons are not debilitated it is frequently 
desirable to lessen the consistency of the mucus. Bearing in 
mind the fact that mucosine is soluble in the alkalies and 
their carbonates our way is clear, and clinical experience has 
shown the efficacy of this rational mode of treatment. In- 
halation is probably the best mode of administering the rem- 
edy when it is desired to lessen the consistency of pulmonary 
mucus. In some diseases of the stomach, also, as in chronic 
ulcer and chronic gastric catarrh there is a hypersecretion of 
tough mucus and the same treatment by alkalies is indicated. 
—{Niemeyer’s Practice, Vol. 1st, jpyp. 498-499). In treat- 
ing chronic gastric catarrh, however, the urine should fre- 
quently be tested for oxalate of lime, which is very frequently 
present in the urine in this disease, and if this is present the 
alkaline treatment of the catarrh is contra-indicated. In 
some forms of diarrhoea and dysentery, also, there is a secre- 
tion of thick tenacious mucus, which it is desirable to dis- 
solve. Alkalies are again indicated here on the same grounds. 
The mucus of the vagina is slightly acid ; that of the cervix 
uteri slightly alkaline.—(Sim’s Uterine Surgery, j). 379). 
This eminent female surgeon found that the spermatozoa were 
frequently killed by an excess of acid or of alkali in the fe- 
male sexual passages, lie tested the secretion with litmus, 
and if it quickly turned to a deep pink, he advised alkaline 
injections; and he mentions two cases in which conception 
occured after this treatment when other means had failed. 
The same distinguished surgeon says (loc. cit., jp. 385), that 
there is frequently a muco-purulent discharge from the cervix 26 
Value of Chemistry to the Medical Practitioner. 
uteri wliicli kills the spermatozoa. Mr. Swann, of Paris, 
found that a solution of hydrochloric acid was the only chem- 
ical which had the power of dissolving it which did not at 
the same time kill the spermatozoa. The proportions used 
by Sims were as follows : 
.£? Hydrochloric Acid, F. dra. i. 
J Distilled Water, F. dra. vii. 
M. 
A teaspoonful of this solution in a pint of tepid water was 
to he thrown in to the vagina night and morning. 
Croup and Diptheria.—Besides the morbid conditions of 
mucus, the consideration of croup and diptheria should pro- 
perly be taken up in this connection, because the fibrinous 
exudations which are characteristic of these affections usually 
occur on mucus membranes. In both of these diseases, suffo- 
cation is to be apprehended, as the air tubes frequently become 
blocked up with the exudation. The indication of treatment, 
therefore, is to dissolve this tough exudation, which consists 
chiefly of fibrin. We have seen, in a previous section, that 
the fibrin of the blood is held in solution in that fluid by am- 
monia, and this agent is highly extolled by Dr. Daguillon, of 
Oran, as a remedy for croup and diptheria.—(Gazette lleb- 
domadaire, Ido. 30, 1870). lie applies it directly to the ex- 
udation by means of a sponge, and tetates that in his hands it 
has proved very beneficial; not only dissolving the exudation 
already present, but preventing any further formation of the 
false membrane in the throat. Dr. Steiner, and Dr. Adolph 
Weber, both recommended lactic acid as a solvent for the ex- 
udation, and the former speaks in high terms also of lime 
water. Lime water wras first used by Dr. Steiner, after trach- 
eotomy, to cleanse the tubes, and he injected it up through the 
opening in the trachea to dissolve the false membranes in the 
larynx. Finding that no bad consequences resulted from 
this, he injected it downwards into the larynx before trach- 
eotomy was performed, with the happiest results. Weber ad- 
dministered lactic acid by inhalation, in the dose of fifteen 
or twenty drops of the acid to halt a fluid ounce of water. Value of Chemistry to the Medical Practitioner. 
27 
Together this he administered carbonate of soda, by the 
stomach. 
The diptheritic exudation way occur also on the conjunc- 
tiva, and give rise to ulceration of the cornea, from the pres- 
sure on the vessels, cutting off the supply of nutriment.— 
(Stellwag, on the Eye,p. 301). Under these circumstances, 
lactic acid or lime water are indicated. The latter should 
never be used, however, when there is an ulcer of the cornea 
present. Membranous enteritis (DaCosta) is probably a 
diptheritic formation, although Dr. II. 13. Ilare states, that 
the membrane corresponds most nearly with mucus. It is 
soluble in caustic alkalies and in sulphuric acid. 
MILK. 
A knowledge of the chemical composition of the milk of 
the human species, and that of the inferior animals, is of very 
great importance to every physician who treats the diseases 
of infants and children. The composition of human milk, and 
that of the cow, the ass, the goat, and the ewe, is given in the 
table below, which is taken from West, on diseases of chil- 
dren, p. 443 : 
Man 
Cow • 
Ass 
Goat 
Ewe 
11111 
8S3SS 
SP. GRAVITY. 
Hill 
FLUIDS. 
110 92 
135.94 
109.88 
155 10 
107.68 
SOLIDS. 
43 64 
38.03 
50.46 
36.91 
39.43 
SUGAR. 
i 26.66 
! 36.12 
' 18.53 
i 56.87 
1 54.31 
BUTTER 
39 24 
55.15 
36.65 
55.14 
69.78 
CASEIN E 
AND 
EXTRACTIVE. 
1.38 
6.64 
5.24 
6.18 
7.16 
INCOMBUSTIBLE 
- SALTS. 
The milk of all animals, varies of course, at different times, 
but the table given above shows the average composition. 
When the secretion of milk in the human female is scanty, 
electricity is sometimes of service in increasing it. When it 
becomes necessary to raise a child by hand, that diet should 
1)0 selected which most nearly corresponds with its natural 
food. Cow’s milk, from the facility with which it is obtained, 
is most generally substituted for the mother’s milk, but as a 28 
Value of Chemistry to the Medical Practitioner. 
general rule it is mixed with an equal quantity of water, or a 
mixture is made of one-third milk and two-thirds water. In 
nearly all books on the subject of childrens’ diseases we find 
the very great dilution of milk advised. It is evident, on a 
moments reflection, that this is an extremely irrational mode 
of preparing a substitute for the natural food of the infant. 
The child has to take a much larger quantity into the stomach 
to get a proper supply of nourishment, and this overloading 
of the infant’s stomach is the starting point to numberless 
ailments. It will be seen by reference to the table, that cow’s 
milk has more of all the solid constituents, except sugar, and 
the aggregate amount of the solids in cow’s milk is rather 
greater than in human milk. Cow’s milk containing about 
two and a-half per cent, more solids than that of the human 
female. Besides this quantitative difference, there is a qual- 
itative difference between human milk and that of the cow. 
This difference consists in the casein of human milk coagu- 
lating in small floculi, while that of cow’s milk coagulates in 
large lumps. This coagulation in lumps prevents its proper 
solution by the gastric juice ; and it passes out of the stom- 
ach to act as an iritant to the mucous membrane of the bowels. 
To prevent this coagulation in lumps, Meigs and Pepper, and 
also Dr. Eustace Smith, advise the administration of gelatin, 
to act mechanically by separating the particles of caseineand 
causing it to coagulate in smaller particles. The best artifi- 
cial food for infants then seems to be cow’s milk with a 
small quantity of water, or what is better, because it is a solvent 
for caseine, lime water added to it and a little gelatin. 
TEARS.. 
The tears consist of water, 99.06. Solids, 00.94. No 
chemical changes occur in it as far as we know. 
The sebaceous matter is an oeaginous fluid, having, ac- 
cording to Esenbeck, (Wilson on diseases of the Shin, Lon- 
don edition, y>. 50.) tire following composition : 
SEBACEOUS MATTER. Value of Chemistry to the Medical Practitioner. 
29 
Fat, 24.2 
Osmazone, with traces of oil, - - - 12.6 
Watery Extractive, - - - - 11.6 
Albumen and Caseine, - 24.2 
Carbonate of Lime, - 2.1 
Phosphate of Lime, . - - - - 20.0 
Carbonate of Magnesia, - - - - 1.6 
Acetate and Muriate of Soda and loss, - - 3.7 
100.0 
The secretion of sebaceous matter is sometimes excessive 
and sometimes diminished in quantity. When excessive, the 
use of alkaline washes has been recommended by Wilson, with 
the view of forming a soap by the union of the alkali with 
the oil and fat of the sebaceous matter. When diminished in 
quantity, it is necessary to furnish some substitute in order to 
lubricate the skin and keep it soft. Glycerine is very gene- 
rally used for this purpose. Changes doubtless occur in the 
quality of the sebaceous matter, but with our present knowl- 
edge but little can be said on this point. Wilson describes a 
qualitative change in this secretion which he called stearrhoea 
nigricans. I)r. Owen Rees examined the secretion and found 
it to consist of carbon, iron, lime, albuminous matters, fatty 
matter, and chloride and phosphate of soda. 
The saliva is secreted chiefly by the parotid, sub-maxillary 
and sub-lingual glands. Its composition according to Bidder 
and Schmidt, Flint’s Physiology, vol. 2d, p. 171, is as follows : 
SALIVA. 
Water, - 995.1 G 
Epithelium, - 1.62 
Soluble Organic Matter, - 1.34 
Sulpho-cyanido of Potassium, - - . 0.06 
Phosphate of Soda, Lime, and Magnesia, - 0.98 
Chloride of Potassium and Sodium, - - - 0.84 
1,000.00 
The function of saliva in the human species is not definitely 
known, Some physiologists say it ]ias only a mechanical 30 
Value of Chemistry to the Medical Practitioner. 
function, while others contend that it is one of the means by 
which starch is converted into sugar. It certainly has the power 
of causing this conversion, but it is generally believed that the 
gastric juice is the chief agent in tin's transformation. Noth- 
ing is known concerning the composition of saliva in diseases 
which is of any clinical significance. 
GASTKIC JUICE. 
The gastric juice is the fluid secreted by the gastric folli- 
cles of the stomach, and it is intended for the digestion of 
nitrogenized articles of food. Its composition according to 
Dalton, is as follows : 
Water, ------ 975.80 
Organic Matter, - 15.70 
Lactic Acid, ----- 4.00 
Chloride of Sodium, - 1.70 
Chloride of Potassium, - - - 1.08 
Chloride of Calcium, .... 0.2q 
Chloride of Ammonium, - - - 0.05 
Phosphate of Lime, .... 1.48 
Phosphate of Magnesia, - - - 0.04 
Phosphate of Iron, - - - - 0.05 
1,000.00 
Many physiological chemists have found hydro-chloric in- 
stead of lactic acid in the gastric juice. Others have thought 
the acidity was owing to the acid phosphate of lime. The 
general opinion at the present day is in favor of lactic acid. 
All agree in the presence of some acid and it is a fact well 
known to every practitioner of medicine that it is sometimes 
present in excess. Whether it is a hypersecretion of the acid 
principle alone, or whether the gastric juice itself is secreted 
in abnormal quantity, is not determined. The former is pro- 
bably the correct explanation. There may be an excess of 
acid in the stomach from other causes, as when a child takes 
food into its stomach which it is unable to digest properly, 
and which by decomposition forms an excess of acid. This 
acid dyspepsia of children has been very ably described by Dr Value of Chemistry to the Ifedical Practitioner. 
31 
Eustace Smith in the American Journal of Obstetrics, &c., for 
1872. In other cases the quantity and quality of the gastric 
juice may he normal, hut owing to an inflamed and irritated 
state of the mucous membrane of the stomach, the normal 
juice becomes too irritating. This is probably the state of af- 
fairs in pregnancy, and the beneficial action of magnesia and 
other antacids is doubtless owing to their power of counter- 
acting the acid principle of the gastric juice, and thus render- 
ing it less irritating. In all cases when the acid is in excess, 
or when the normal amount is too irritating, antacids are in- 
dicated. The carbonates of the alkalies are probably most 
generally employed.—(dfiemeyer). Lime water is very po- 
pular with many physicians, especially when combined with 
sub-nitrate of bismuth. Headland states that the action of 
bismuth is purely mechanical, but the experience of the great 
majority of physicians is in favor of its being an antacid. 
Effervescing mixtures containing a tartrate or citrate of potash 
or soda have been advised, and lemonade is highly extolled 
by some physicians. The citrate of potash of the lemon juice 
is converted into the carbonate, which in its turn is decomposed, 
the potash uniting with the acid of the stomach and the car- 
bonic acid being discharged by eructation. 
The organic principle of the gastric juice, “pepsin,” is pe- 
culiar to that fluid, and is necessary for digestion. This sub- 
stance may sometimes be in excess in the gastric juice, but 
nothing is known of such a condition if it ever occurs. It is 
frequently, however, diminished in quantity, and this diminu- 
tion may be either temporary or permanent. Drs. Fenwick 
and Flint, Sr., have proved quite conclusively that the patho- 
logy of Addison’s disease is atrophy of the gastric tubules. 
In this disease the secretion of gastric juice is, of course, di- 
minished in proportion to the number of tubules affected. 
Life could possibly be jfrolonged in these cases by the admin- 
istration of an artificial gastric juice. So far as I know, how- 
ever, nothing of the kind has ever been tried. When the 
diminution in the secretion is only temporary, as after attacks 32 
Value of Chemistry to the Medical Practitioner. 
of severe illness, the administration of pepsin has been tried 
with decided benefit ; and if the “great expectations” con- 
cerning the benefit to be derived from pepsin have not been 
fully realized, it is probably owing, in part, to the fact, that 
much of the pepsin now in use is obtained from the stom- 
ach of the cow an herbivorous animal, and is given to take 
the place of that of man an omnivorous animal. 
PANCREATIC JUICE. 
The pancreatic juice is secreted by the pancreas. Noth- 
ing is known concerning the chemical composition of this 
fluid in the human subject. That obtained from the dog has 
been analysed and the composition of that of man has been 
inferred from this. It is scarcely necessary to give the com- 
position of this fluid taken from the dog. It contains a much 
larger proportion of organic matter than any of the other 
fluids, and this matter is called pancreatine, and is the prin- 
ciple agent in the digestion of fat which is converted into an 
emulsion by it. This substance is undoubtedly present in 
human as well as in canine pancreatic juice, and its function 
is the same in all animals. Nothing definite is known con- 
cerning the abnormal condition of this fluid. It is highly 
probable, however, that some cases of “fatty diarrhoea’’ are 
owing to a deficient secretion of pancreatic juice, and pancre- 
antie has been already used in such cases with decided benefit. 
Concerning the intestinal juice even less is known than 
about pancreatic juice. Its reaction in tlie dog is alkaline and 
its function seems to be to assist in the conversion of starch 
into sugar. Nothing is known concerning its chemical com- 
position in man, and, of course, nothing can be known con- 
cerning its abnormal conditions. 
INTESTINAL JUICE. 
BILE. 
The bile is secreted by the liver. Its most important con- 
stituents are glyco-cholate and tauro-cliolate of soda. Its 
function is not definitely known, but it is certainly, in some Value of Chemistry to the Medical Practitioner. 
33 
way, connected with the process of digestion, for when the 
secretion of bile is checked from any cause, or its entrance 
into the intestine prevented, imperfect and painful digestion 
is the result. 
Medicines to promote the secretion of bile have been used 
from time immemorial, but not with any very definite views 
a3 to their modus ojperandi. Headland (loc: cit.), states that 
quinine has been found of great benefit in acliolia, and he 
thinks it acts by taking the place of the taurine of bile, to 
which it is precisely similar in its chemical composition. As 
taurine can now be manufactured synthetically from sulphu- 
ric acid, alchohol, and ammonia (Odling), at a very low price, 
it would be advisable, if Mr. Headland’s theory be correct, to 
use tliis artificial taurine in these cases in the place of qui- 
nine. If the acliolia were prolonged, however, substances to 
take the place of taurine would do but little good, as the re- 
tention of cholesterine would cause the most prominent and 
most dangerous symptoms. The presence of the bile pig- 
ments, &c., in other secretions and excretions will be treated 
of while speaking of the fluids in which they are found. 
Choleate of soda has recently been proposed as a remedy 
lor biliary lithiasis, by Prof. Scliiff, on the ground that as 
bile stones usually consist chiefly of cholesterine, and as this 
substance is soluble in choleate of soda, the bile stones can 
thus be dissolved, and their formation prevented. He says 
the treatment has been tried, and found of very decided be- 
nefit. He administers the remedy in the dose of about seven 
and a half grains twice a day, gradually increasing till the 
system becomes saturated. 
SEBUM. 
The secretion of serous membranes is known as serum. 
Its function is to keep the membrane soft and pliable. The 
composition of serum is not definitely known, but it contains 
albumen in large quantity and some chloride of sodium. A 
knowledge of its proximate composition has been utilized by 34 
Value of Chemistry to the Medical Practitioner. 
Er. Peaslee in the operation of ovariotomy. He advises that 
during the operation the hands of the operator be frequently 
bathed in an artificial serum having the following composi- 
tion : 
7? Chloride of Sodium, dra. iv. 
J White of Egg, dra. vi. 
Water, P. iv. 
M. 
So far as we can learn this is the only practical use which 
has been made of a knowledge of the composition of the se- 
cretion of serous membranes. 
The fluids of the organism, which are execretions, arc 
perspiration, urine, and bile. The latter, as wo have before 
stated, has a double office, to assist in digestion and to carry 
off the cliolesterine excreted by the liver. Cholesteraemia 
has been already treated of under the head of the Blood, and 
we shall not refer to it again. 
PERSPIRATION. 
The perspiration is a colorless, watery fluid, having a dis- 
tinctly acid reaction. Its composition, according to Ansel- 
mino, (Simon loc. 374) is as follows : 
Water, ------ 99$.000 
Epidermis and Salts of Lime, - - - .100 
Water Extract and Sulphates, ... 1.050 
Spirit Extract, Chlorides of Sodium and Potash, 2.400 
Alcohol Extract, Acetates Lactates and Free Lactic 
Acid, 1.450 
The gases given off by the skin are, according to Collard 
de Martigny, carbonic acid and nitrogen. The chief func- 
tion of the perspiration is to regulate the temperature of the 
body. When exposed to a high temperature the secretion of 
perspiration is very copious, and in its evaporation and pas- 
sage to the gaseous form, so much heat becomes latent that Value of Chemistry to the Medical Practitioner. 
35 
the temperature of the body is reduced to the normal stand’ 
ard. Besides this function, however, the perspiration has 
another important function, namely, the elimination of effeto 
matters from the system. As we have seen in a previous 
section, the skin is one of the channels for the vicarious elim- 
ination of urea when its elimination by the kidneys is inter- 
fered with. So in rheumatism, the lactic acid is eliminated 
by the skin, and has been found in the perspiration in consid 
erable quantity. Uric acid and urate of soda have also been 
found in the perspiration, and it is highly probable that tlioso 
substances are eliminated by the skin to a certain extent in 
gout. Albumen has been found in the sweat by Anselmino 
and Stark, but the circumstances under which it is present 
are not sufficiently known to lead to any practical results. 
The coloring matter of the bile is present in the perspiration 
whenever from any cause its secretion or its passage into tho 
intestines is interfered with. In all those diseases where the 
“ materics morbi ” is eliminated by the skin remedies are 
indicated which increase the discharge of perspiration. None 
of the diaphoretics have a directly chemical action. Water 
should be drunk in considerable quantity so as to take the 
place of that which passes off as perspiration. The dis- 
ci large of carbonic acid by the skin is not very great, and so 
far as we are aware only one physiologist has drawn any 
practical deduction from it. Claude Bernard advances the 
theory that the greater rate of mortality after amputations 
in the upper part of a limb than in the lower is owing to 
a larger surface for the excretion of carbonic acid being re- 
moved in the former than in the latter. This is simply a 
theory, and requires further examination before any definite 
conclusions can be reached. 
UKLNE. 
The urine is an excretion, and it is in this fluid that the 
eflbte nitrogenized matters are discharged from the system. 
The chemical composition of the urine in health has long 
been known. 36 
Value of Chemistry to the Medical Practitioner. 
According to the analysis of Berzelius, Lehman and 
Becquerel it is as follows : 
Water, ...... 938.00 
Urea, ------ 30.00 
Creatine, 1.25 
Creatinine, - 1.50 
Urates of Soda, Potassa and Ammonia, - - 180 
Coloring Matter and Mucus, ... .30 
Bi-Phosphate of Soda, 
Phosphate of Soda, 
“ * of Potassa, 
“ of Magnesia, 
“ of Lime, 
12.45 
Chlorides of Sodium and Potassium, - - 7.80 
Sulphate of Soda and Potassa, - - - 6.00 
Healthy urine has generally an acid reaction, but as 
shown by Dr. Bence Jones and others it is frequently alka- 
line soon after eating. The specific gravity is about 1020. 
A knowledge of the changes which take place in the urine 
after its discharge from the body, and the order in which 
these changes occur, is absolutly necessary before we can un- 
derstand the abnormal conditions of this fluid ; hence we 
shall consider these changes briefly. 
After standing a few hours the epithelium and mucus are 
deposited in the form of a light flocculent precipitate. The 
next change which takes place is the acid fermentation. This 
is caused by the formation of lactic acid in some way as yet 
not understood. (By reference to the table we see that there 
is no free acid in the urine, the acid reaction being caused by 
the bi-phosphate of soda). The lactic acid decomposes a 
portion of the urates and uric acid is deposited. Oxalic acid 
is also frequently formed during the acid fermentation, and 
this uniting with the lime causes a deposit of crystals of ox- 
alate of lime. After some days the alkaline fermentation be- 
gins when the urea is converted into carbonate of ammonia 
and the earthy phosphates are deposited, and by double de- 
composition the triple phosphate of magnesia and ammonia, Value of Chemistry to the Medical Practitioner. 
37 
find the phosphate of soda and ammonia are formed. These 
salts form crystals which can he seen in all parts of the fluid. 
Having thus taken a short view of the composition of the 
urine in health, and the changes which it undergoes after be- 
ing discharged from the body, we are prepared to study its 
abnormal conditions and their clinical significance. We shall 
consider first those abnormal substances which are in solution 
in the urine and subsequently take up “ urinary deposits.” 
The substances in solution in the urine which are symptomatic 
of disease of some organ of the body are: Albumen, sugar, 
biliary matter, fat, leucine and tyrosine. 
1. Albuminuria.—Albuminous urine according to Nic- 
meyer (Practice of Medicine, Vol. 2,y>. 26,) is generally of a 
pale yellow color, and often exhibits somewhat of an opales- 
cent reflection. As it is more viscid than common urine, on 
account of the albumen which it contains, it is more easily 
made frothy than urine free from albumen, and the froth lasts 
longer. When there is no intercurrent febrile disease the 
specific gravity is remarkably low, and may sink to 1,005. 
The physical characteristics of albuminous urine are very 
variable, but the chemical tests are very simple. When heated 
to 167° Fhr. albumen coagulates if the fluid which contains it 
be neutral or slightly acid. It is also coagulated by the min- 
eral acids. Nitric acid is generally used for this purpose. If, 
however, a very small quantity of nitric acid be added to 
urine containing albumen, and it is then heated, the albumen 
is not precipitated.—(Odling,p. 19-1). In order to avoid any 
mistake the suspected urine should be tested in botli ways. 
Albuminuria is generally a symptom of Bright’s disease of the 
kidneys, but it may bo caused by any form of congestion of the 
kidney. It sometimes occurs during pregnancy, and is then 
a sign that uraemic poisoning is threatened. We have 
already stated that when albumen is present in the urine, 
there is an excess of urea in the blood. The connection be- 
tween albuminous urine and puerperal convulsions is thus ex- 
plained, and the importance of examining the urine during 38 
Value of Chemistry to the Medical Practitioner. 
pregnancy for albumen is ably pointed ont by the late Dr. 
Geo. T. Elliot in his “Obstetric Clinic.” There is probably no 
causative relation existing between the presence of albumen 
in the urine and the retention of urea in the blood. Both are 
doubtless owing to the congestion of the kidneys, and the loss 
of the epithelial lining of the uriniferous tubules.—(Niemeyer). 
The indications of treatment to which the presence of al- 
bumen in the urine give rise have already been treated of 
under the head of “Uraemia.’’ A few rymarks concerning 
the diet suitable in albuminuria, however, are called for in 
this connection. We have seen previously that when albumi- 
nuria exists, the amount of albumen in the blood is below the 
normal standard, and that under these circumstances dropsy 
is liable to occur. We should therefore give food rich in al- 
bumen, to take the place of that drained off by the kidneys. 
Eggs contain albumen in larger quantity than any other ali- 
mentary substance, and owing to the large quantity of in- 
organic alimentary* principles which they contain, are pecu- 
liarly suitable as an article of diet. Milk is also very suitable 
as the casein which it contains is converted into albumen be- 
fore being absorbed. Both eggs and milk are very easy of 
digestion. If the patient is sufficiently strong to digest it, 
meat should be used, as the musculine of meat, like the casein 
of milk, is converted into albumen before being absorbed. 
Vegetable albumen is found most abundantly in turnips, 
carrots, cabbages, &c.—(.Flint’s Physiologo, Vol. lyj>. 51). 
2. Diabetes Mellitus.—Urine, which contains sugar, can 
not be distinguished by the eye from the normal secretion. 
Its specific gravity is, on an average, 1,035. It has a dis- 
tinctly sweetish taste, and like albuminous urine retains its 
froth for some time after being agitated. 
But little of a definite nature is known concerning the func- 
tion of sugar in the animal economy. The general opinion 
among physiologists is that it is in some way connected with 
the production of animal heat. 
In certain conditions of the system sugar Unay appear in Value of Chemistry to the Medical Practitioner. 
39 
the urine temporarily and in small quantity, without being a 
symptom of any serious disease. When it continues for a 
length of time, however, and is present in large quantity, it is 
a symptom of great gravity. The cause of its appearance in 
the urine is unknown ; that there is an increased production 
in the liver is certain, (Flint's Physiology, Yol. 1 , p. 59); and 
it is probable that in some cases, at least, less sugar is con- 
sumed in the animal economy than in a state of health. 
It is a matter of great importance, on account of the prog- 
nosis, to be able to detect sugar in the urine, and various tests 
have been proposed for this purpose. The one in most gen- 
eral use is Trommer’s, which is practiced in the following 
manner: To the suspected fluid add a few drops of liquor 
potassae, to render it distinctly alkaline ; then add a small 
quantity of a moderately strong solution of sulphate of copper, 
and heat the fluid in a test tube ; if sugar be present, a little 
before the boiling point is reached a red precipitate of sub- 
oxide of copper is formed. In Bottger’s' test subnitrate of 
bismuth is used instead of sulphate of copper, and carbonate- 
of soda instead of liquor potassea. A black precipitate is 
formed in this test. There are several other tests, but they 
possess no advantages over those given above. 
As so little is known concerning the physiology and pa- 
thology of the formation of sugar, but little of a definite 
nature can be said concerning the treatment of diabetes mel- 
litus on chemical principles. Under the supposition that 
sugar was converted into lactic acid in the lungs, and then 
united with alkalies to form salts, alkaline remedies were pro- 
posed, and it is thought by some that their use was attended 
with benefit.—(Alint'spractice, p. 81). Acids to prevent the 
transformation of amylum into sugar have been proposed, as 
has also yeast, to act as a ferment, and cause the sugar pro- 
duced in the liver to be converted into,lactic acid. None of 
these proposed remedies have come up to expectations, al- 
though they have sometimes seemed to be of service. Cantani 
recommended lactic acid. He thought diabetes was owing to 40 
Value of Chemistry to the Medical Practitioner. 
the formation of a substance called paraglucose, which could 
not be burnt off, and consequently the fat and albumen were 
burnt olf to keep up the animal heat. Lactic acid has been 
extensively used and highly extolled by most physicians who 
have used it.—See an article in Edinburgh Med. Journal for 
December,\iJl\,by Dr. G. W. Balfour). Skim milk, proposed 
by Dr. Arthur Scott Donkin, would act by virtue of the lactic 
acid which it contains. 
The diet is agreed on all hands to be of the utmost im- 
portance. All saccharine and amylaceous articles should be 
avoided. Meat, eggs, lisli, &c., are useful. A small quantity 
of bread daily is very necessary to the comfort of the patient, 
and does no serious harm. The following list of vegetables, 
arranged in order according to their proportion of starch, is giv- 
en on the authority of Payen, in Flint’s physiology, Vol. 2d, p. 37: 
Parsnips, which contain in their natural condition G, and dcs- 
sicated 29.38 parts per 100 of starch ; carrots, pods of string 
beans, turnips. Starch is found principally in the cortical 
portion of these roots. Cabbage; the presence of starch is re- 
cognized in very small quantity in the ribs of the leaves. 
Cauliflower; in the upper extremity or head are slight traces, 
No starch was found in romain, lettuce, chiccory, in the leaves 
of sorrel, spinage, asparagus, articliauts, leeks, nor in the 
large early white onion. Sugar is found as such in some of 
the articles in the foregoing list in considerable quantity. 
Onions and turnips both contain sugar in some quantity, and 
parsnips and carrots contain both sugar and starch. 
3. Biliary matter is present in the urine in jaundice from 
whatever cause the disease may have arisen. It is occasion- 
ally of importance, in a diagnostic point of view, to determine 
the presence or absence of the coloring matter of the bile. It 
is doubtful whether the urine as voided ever contains more 
than a trace of the true biliary salts.—(Odling). The two 
most common tests for the biliary coloring matter in the urine 
are known respectively as the nitric acid test and Heller’s 
test. Value of Chemistry to the Medical Practitioner. 
41 
“In the nitric acid test a little of the urine, previously con- 
centrated if necessary, is poured on a white slab and a few 
drops of nitric acid then let fall upon it. Where the acid comes 
in contact with the biliary urine there is a peculiar play of 
colors produced—green, pink, violet and yellow being easily 
recognizable.”—(Odling). 
In Ilellpr’s test it is necessary that albumen be present in 
the urine, and hence white of egg has to be added. On the 
addition of nitric acid a cloud is formed of a somewhat bluish 
color. When a sample of urine containing biliary matter 
is exhibited, a yellow scum is formed on the surface.— 
Galloway s Qualitative Chemical Analysis, p. 315). 
4. Frerichs found that in “Acute yellow atrophy of the 
liver,” leucine and tyrosine were always present in the urine 
in largo quantity.—(Niemeyer). Leucine lias been found by 
different chemists, in nearly every tissue of the body, but the 
only one which contains it in health, so far as we know at 
present, is the spleen. According to Iloppe-Seyler, it is 
generally produced by the splitting up of albuminoid sub- 
stances. The observations of this chemist, and of others, 
render it highly probable that further chemical examination 
of the faeces for this substance, and also for tyrosine, will 
throw much light on a class of affections (diseases of the pan- 
creas), the nature of which is now very imperfectly understood. 
In an able article in the American Journal of the Medical 
Sciences, for January, 1872, by Dr. James Tyson, of Pliladel- 
phia, we find the following tests for leucine : It crystalizes 
in spherules which are generally colored yellow by the coloring 
matter of the bile. If a portion of the deposit from the urine 
be heated in a dry tQst-tube, over a lamp, and leucine is pre- 
sent, it will be converted by boiling into an oily drop, and 
emit an odor like burnt horn. Another test is : if leucine be 
heated in an open tube to the temperature of 170° Fhr. it 
sublimes and gives off floculent wooly masses. This test is 
very characteristic. 
5. The same remarks which were made relative to leucine 42 
Value of Chemistry to the Medical Practitioner. 
will apply to tyrosine. The pathological conditions under 
which they most frequently appear in the urine are in atro- 
phic conditions of the liver. There are several tests for tyro- 
sine given by Dr. Tyson in the paper referred to above, but 
we shall only give one or two of them here. Hoffman’s test 
is practiced in the following manner : Dissolve a small quan- 
tity of the suspected crystals in a test-tube ; add a few drops 
of a solution of nitrate of mercury and heat to boiling. If ty- 
rosine is present the liquid will soon change to a rosy red, 
and later a red precipitate takes place. On the application of 
heat to tyrosine it gives off the odor of burnt horn, but does 
not sublime as does leucine. Urine which contains these sub- 
stances is' generally deficient in urea, and death seems gene- 
rally caused by uraemic poisoning. Their presence generally 
indicates a speedy course for the disease in connection with 
which they appear 
Medicines to promote the vicarious elimination of urea 
are generally indicated. With this exception there seems to 
be no special therapeutical indications. The diseases in which 
they appear in the urine are nearly always fatal. 
6. Fat is occasionally present in the urine. It is easily 
detected by the microscope. It appears as round shining 
globules with dark edges. The presence of kiestein, a fatty 
substance, in the urine was formerly considered characteristic 
of pregnancy, but this has been disproved. It is of no clinical 
significance.—(See Elliot’s Obstetric Clinic). 
Urinary Deposits—Urinary deposits may be either inor- 
ganic or organic compounds. The most common forms of 
deposit are urate of ammonia, earthy phosphates, oxalate of 
lime, and uric acid. These may be present cither singly or 
combined with each other. The following table is given by 
Bowman, (Medical Chemistry, jp. 3) for facilitating the exami- 
nation of urinary deposits by means of chemical tests : 
(1) The sediment dissolves when warmed ; {Irate of Am- Value of Chemistry to the Medical Practitioner. 
43 
monia. Not soluble wlien warmed ; but, (2) soluble in acetic 
acid ; Earthy Ldiosp>hates. Insoluble in acetic acid ; but, (3) 
soluble in dilute hydrochloric acid ; Oxalate of Lime. In- 
soluble in dilute liydrocloric acid ; but, (4) purple with nitric 
acid and ammonia ; Uric Acid. 
If the deposit proves to be none of the above, it must be 
one of the following : 
(5) Greenish yellow deposit easily diffused on agitation ; 
Pas. (6) Ropy and tenacious ; Mucus ? (T) Red or brown ; 
not soluble when warmed; the fluid portion coagulable by 
heat and nitric acid ; Blood. (8) Soluble in ammonia ; the 
solution leaving on evaporation hexagonal crystals ; Cystine. 
(9) Yellowish sediment ; soluble when warmed ; Urate of 
Soda f (10) Ether yields after agitation an oily or fatty re- 
sidue ; Fatty Matter. (11) Milky appearance ; Chylous 
Matter. 
Bowman also gives at pp. 119-120 a table for facilitating 
the microscopical examination of urinary deposits which are 
given below. 
1. If the deposit is crystaline : 
(1) Lozenge shaped ciystals ; Uric Acid. (2) Stellae, or 
three sided prisms ; Trip>lc Phosphate. (3) Octahedra, or 
dumb-bells ; Oxalate of Lime. (4) Rosette-like tables ; Cys- 
tine. 
2. If amorphous or rounded particles : 
(1) Soluble when warmed ; Urate of Ammonia. (2) Sol- 
uble in acetic acid ; Phosphate of Lime. (3) Yellowish grains; 
Urate of Soda. (4) Round globules with dark edges ; Fatty 
Matter. (5) White and milky ; Chylous Matter. 
3. If organized particles : 
(1) Granulated corpuscles in stringy aggregation ; Mucus. 
(2) Irregularly shaped scales ; Epithelium. (3) Detached 
granulated corpuscles ; Pus. (4) Blood corpuscles; Blood. 
(5) Spermatozoa ; Semen. 
A table for facilitating the examination of urinary de- 
posits is given by Galloway (loc : cit, pp. 317-320), but it is 44 
Value of Chemistry to the Medical Practitioner. 
neither so complete nor so simple as the table given above, 
and we think it entirely unnecessary to reproduce it here. 
We shall now proceed to study each of these deposits in 
the order in which they are given in the “ table for facilitating 
the examination of urinary deposits by means of chemical 
tests.” 
Uric Acid Diathesis.—Urate of ammonia generally 
occurs in acid urine. It is important because one form of 
calculus is composed of it. This form of calculus is com- 
bustible ; soluble in nitric acid yielding uric acid reaction ; 
soluble also in boiling water and carbonates of alkalies. 
Bearing this fact in mind, alkalies and their carbonates 
would seem to be indicated. The Vichy water which con- 
tains carbonates of lime, soda and magnesia, sulphate of 
soda, chloride of sodium, and some free carbonic acid, is 
highly recommended by Erichsen. He also speaks favor- 
ably of the use of bicarbonate of potash and nitre. The car- 
bonate of lithia and lithia water have been much used of 
late years.—(See section on Gout). When administering al- 
kalies in the uric acid diathesis, the urine should be frequently 
tested to see whether it is acid or alkaline, else the uric acid, 
diathesis, may give place to the pliosphatic. Calculi consist- 
ing of alternate layers of different chemical compounds are by 
no means rare. Acid fruits are contra-indicated in the uric 
acid diathesis as a general thing, except those acids, such as 
lemon juice, which contain a large amount of potash. The 
malates, tartrates, citrates, &c., are converted into carbonates 
in the stomach, and enter the blood as such. Bird says (Uri- 
nary Deposits, p>- 132), that roasted apples, strawberries, cur- 
rants, and some other fruits may occasionally be employed 
with advantage, and I have, on one occasion, seen great benefit 
result from the use of grapes. 
Oxalic Diathesis.—The oxalic diathesis according to 
Golding Bird is one of the most common. It occurs in urine 
in which there is an abnormally large quantity of urea, and 
Bird thinks the oxalic acid is formed sometimes from urea, by Value of Chemistry to the Medical Practitioner. 
45 
the oxidation of this substance. Oxalate of lime calculi are 
quite common. They generally, however, have a nucleus of 
uric or urate of soda. They are incombustible and in- 
fusible ; and are soluble slowly in nitric and hydrochloric 
acids without effervescence. Oxalate of lime in persons in 
good health does not enter the blood, or reach the urine, on 
account of its insolubility. Certain vegetables, such as the 
rhubarb plant, sorrel, tomatoes and turnips, contain enough of 
a soluble salt of oxalic acid to cause a deposit of oxalate of 
lime in the urine. Onions, although containing a salt of ox- 
alic acid, do not cause oxaluria, because the oxalate which 
they contain is insoluble. 
The treatment should be directed to causing the solution 
of the deposit of oxalate of lime. For this purpose nitric and 
hydrochloric acid, or a mixture of the two, should be given, 
and their use kept up some time. 
The vegetables previously mentioned containing a large 
quantity of oxalic acid, and also those containing sugar in large 
quantity, should be avoided.—(Gross’ System of Surgery, 
Vol. 2,y>. 760). 
Phosphatic Diathesis.—The phosphatic deposit may oc- 
cur in three forms: (L) Triple or ammonio-magnesian phos- 
phate. (2) Phosphate of lime , and (3), a mixture of the 
above. 
The urine in this diathesis is either neutral or feebly acid in 
reaction. It frequently becomes alkaline, however, soon after 
being passed. The phosphatic are the most common forms of 
calculi. They are soluble in dilute hydrochloric and nitric 
acid, and the triple phosphate is also soluble in acetic acid. 
The mineral acids, especially nitric, are recommended in this 
diathesis. 
Attention to the general health is of the utmost importance 
in all these affections, but as chemistry has nothing to do with 
the general treatment, it does not claim our attention. 
Pyuria.—Pus is usually found*in acid or neutral urine. 
It is symptomatic of suppurative disease of the kidneys or 46 
Value of Chemistry to the Medical Practitioner. 
urinary passages. When it occurs it is in the form of a green- 
ish layer at the bottom of the vessel, and can easily he dif- 
fused through the urine. If the urine be alkaline, however, 
or if an alkali be added to it, the pus becomes coagulated, 
and either hangs in shreds or forms a coagulum ot greater or 
© © © 
less firmness. The microscopic characters have been previ- 
ously given. The therapeutical indications will of course 
depend upon the nature of the disease under wicli the patient 
labors, and lienee no general rule gan be given in this connec- 
tion with regard to treatment. 
Urine Containing- Mucus.—Mucus is generally present 
in the urine in very small quantity. When present in large 
quantity it is generally symptomatic of inflammation of the 
bladder, either sub-acute or chronic. It differs from pus in 
being in shreds and strings even when the urine is acid. When 
acetic acid is added to urine containing mucus, the fluid por- 
tion of the mucus coagulates into a thin corrugated membrane. 
{Bird). The presence of mucus gives rise to no special in- 
dications of treatment. 
Haematueia.—Blood may be present in the urine either 
from disease or injury of the kidneys or urinary passages. It 
is generally easily detected by the microscope, and by the 
spontaneous coagulation of the fibrin. Chemistry bears no 
part in its treatment that we need consider in 'this connection. 
The modus ojoerandi of astringents will be briefly considered 
elsewhere. 
Cystine in the Urine.—Cystine is not a common form of 
urinary deposit, but is of interest from the fact that occasion- 
ally calculi occur, which are composed of it. It generally ap- 
pears as a white or pale fawn-colored powder. It is soluble 
in the mineral, but insoluble in the vegetable acids. Is also 
freely soluble in ammonia and the fixed alkalies and their car- 
bonates, but is insoluble in carbonate of ammonia. On being 
kept for a short time, urine becomes covered with a 
greasy looking pellicle. The presence of this substance in the 
urine seems to be hereditary and generally intimately con- Value of. Chemistry to the Medical Practitioner. 
47 
nected with scrofula. Too little is known on the subject for 
any definite rules to be laid down concerning the treatment; 
bearing in mind, however, its ready solubility in the mineral 
acids and also in ammonia and the alkalies, these would seem 
to be indicated ; the acids when the urine was alkaline, and 
vice versa. Epithelium and urinary casts are occasionally 
present in the urine, and may be detected by the microscope. 
They do dot demand our attention in this connection, how- 
ever. 
ZP-A-IRT IX. 
Having now completed the consideration of the fluids of 
the organism, we will proceed to study the solids. Only those 
will be considered, however, a knowledge of whose chemical 
composition is of service to the medical practitioner. Faeces, 
although semi-solid, will be considered under this head. 
We propose, then, to study the solids of the organism in the 
following order : 
(1) Nervous tissue. (2) Muscular tissue. (3) Bony tis- 
sue. (4) Ilair. (5) Coats of arteries. (6) Faeces. 
NERVOUS TISSUE. 
The chemical composition of nervous matter is a subject to 
which very little importance has been attached, but it is one 
which we are convinced is well worth investigation. We learn 
from Turner’s Chemistry that nervous matter consists of 80 
per cent, of water, 7 per cent, of albumen, and that the re- 
maiftder is fatty matter. It is to this fatty matter that we will 
direct our attention. 
The fatty matter is in the form of two acids, cerebric and 
oleo-jphosphoric. 
Cerebric is distinguished from the other fatty acids by 
containing nitrogen and phosphorus. The other acid, oleo 
phosphoric, as its name implies, is composed of phosphorus 
and fat. The precise function of these acids is unknown. 
Many chemists have found an excess of the earthy phosphates 
in the urine after severe and prolonged mental exertion. It 48 
Value of Chemistry to the Mediccd Practitioner. 
is true that this view, of the discharge - of phosphorus by the 
kidneys has been opposed {See American Journal Medical 
Sciences, April, 1870,pp. 506-507); but we think the grounds 
of opposition are insufficient. It has been found, too, that if 
phosphorus be supplied in some form, it acts as food for the 
overtasked brain and refreshes the weary mind. Dr. Judson 
B. Andrews, of the Hew York State Lunatic Asylum, in the 
American Journal of Insanity for October, 1869, gives the 
result of his experience with phosphoric acid. It acts, he says, 
as a special nervous stimulant. Dr. Wm. A. Ilarmnond, ar- 
guing from the chemical composition of the brain, and from 
the fact that phosphorus is discharged in large quantity by 
the kidneys, after severe mental effort, has proposed phospho- 
rated oil in the treatment of mental depression and wakeful- 
ness brought on by over-exertion of the mind, and its use lias 
been attended with great benefit in nearly every case. This 
form of disease is confined chiefly to professional men, a1id 
doubtless sweeps many of our ablest thinkers to the grave. It 
is probably to this cause that Horace Greeley owed his death. 
Let us bear in mind also that nervous matter contains a 
large proportion of fat. This fact suggests valuable therapeu- 
tical indications. That neuralgia is frequently owing to a 
want of some of the normal constituents of the nervous mat- 
ter cannot be doubted, and Dr. F. E. Anstie, in “Diseases 
of the Spine and of the Nerves,” says he has found fat of very 
great benefit in the treatment of this disease. lie usually 
gives cod-liver oil, but if this can not be borne he gives cream. 
The writer of this article has been, from a child, subject to 
violent attacks of frontal neuralgia, and he has found that 
when he habitually takes a large amount of butter with his 
food the attacks arc less frequent and less severe. 
MUSCULAR TISSUE. 
Muscular tissue contains about 17 per cent, of fibrin, cells, 
vessels, and nerves, and about 2.30 per cent, of albumen. It 
is unnecessary to give the composition of muscular tissue in 
full, as we shall only have occasion to speak of the fibrinous Value of Chemistry to the Medical Practitioner. 
49 
and albuminous principles. We propose to consider these 
principles briefly in connection with the modus operandi of 
astringents. Mialhe, (Chemie applique a la physiologie et a 
la therapeutique, p. 646) says .* “Vous les astringents appar- 
tiennent a la classe des coagulants ; cest-a-dire a la classe des 
agents chemiques, susceptildes d’entrer en combinaison avec 
les elements albumineux du sang et de former avec eux un 
compose in-soluble.” Headland says that not only have as- 
tringents the power of coagulating albumen, but also of caus- 
ing the coagulation of librine, and he thinks that it is by this 
coagulation and consequent hardening that astringents act. 
The modus op>ei'andi of ergotine is not very definite ; it cer- 
tainly has the power of lessening the calibre of bloodvessels, 
and its action as a parturifacient is universally acknowledged, 
but it is impossible, for obvious reasons, that the very great 
C3ntraction of the uterus, which frequently occurs under its 
use, should be owing entirely to the coagulation of the fibrin 
and albumen contained in muscular tissue. Mialhe confesses 
his inability to account for its action on chemical principles. 
The chemical composition of hone and the alterations which 
take place in it in disease, have been very carefully and tho- 
roughly studied. The constituents of bone to which we have 
to direct our attention are only two—the phosphate and the 
carbonate of lime. The former is by far the most important 
inorganic principle of bone. Lassaigne found that it was pre- 
sent in healthy bone in the proportion of 400 parts per 1,000. 
It is intimately associated with the organic matter of bone, 
and can only be separated from it by chemical means. When 
allowed to stand in hydrochloric acid the bone becomes flexi- 
ble in consequence of the phosphate of lime being decomposed 
and withdrawn from combination with the organic matter. 
Bostock found that phosphate of lime was present in the ver- 
tebra of a rachitic patient in the proportion of 136 parts per 
1,000. The practical inportance of a knowledge of this fact 
is apparent at a glance. The indication is to supply phosphate 
BONE. 50 
Value of Chemistry to the Medical Practitioner. 
of lime. The administration of pure phosphate of lime has 
not been attended with as much benefit as was expected from 
it. The Zacfo-phosphate is said to answer admirably as a re- 
medy in this affection.—{Parry, in American Journal Med- 
ical Sciences, April, 1872). 
Hail* contains nearly 5 per cent, of sulphur. It also con- 
tains a large proportion of oil. The use of sulphur in pro- 
moting the growth of the hair is well known. Its modus 
operandi in so doing is a matter about which there is great 
difference of opinion. Some physicians think it acts simply 
as an irritant; while others think that it acts by furnishing 
sulphur to the hair follicles. Both views of its action are sim- 
ply theories, and are given here for what they are worth. 
HAIR. 
ARTERIES. 
A deposit of calcareous matter occasionally occurs in the 
coats of the arteries, especially the middle coat. It is, accord- 
ing to Rindfleisch (Pathological Histology, p. 215), purely a 
calcareous deposit ; this observer has never detected any- 
thing “which answered to the anatomical dignity of a bone 
corpuscle.” If it depends upon a co-existing osteo-malacia, 
wliicli Green (Pathology and Morbid Anatomy, yip. 74-75,) 
says is a common cause of the disease, the mineral acids can 
not be used, but if it were from a superabundance of calcare- 
ous salts in the blood, without structural change of bone, the 
mineral acids, particularly hydrochloric, would seem to be 
indicated. 
Chemical examination of the faeces lias been very much 
neglected by both physiologists and pathologists ; and yet there 
is no subject which is more worthy of study, or a knowledge of 
whose chemical composition would better repay the practical 
physician. The vicarious elimination of urea and some other 
excrementitious principles by the alimentary canal, have al- 
ready been spoken of; and we have also briefly considered 
FAECES. Value of Chemistry to the Medical Practitioner. 
51 
the fatty diarrhoea, which is probably indicative of disease of 
the pancreas, and for the relief of which pancreatine is used. 
With our present ignorance concerning the physiology of the 
faeces, but little more can be said about the information to be 
derived from it relative to pathology. We have no doubt, 
however, that the time will soon come when fecal pathology 
will occupy as prominent a position as urinary pathology now 
does. 
III. 
POISONS. 
A thorough knowledge of the chemical relations of the dif- 
ferent poisons is of great service in the practice of medicine ; 
but the tests for the various poisons, while it is a subject of 
the greatest moment, on which often hang the issues of life 
and death, are not generally made by the medical practitioner, 
but by chemical experts. For this reason we do not think it 
necessary to consider the tests for poisons in this paper. Gal- 
loway’s “Manual of Qualitative Chemical Analysis’’ describes 
the tests for the various poisons very fully, and yet presents 
them in a form which is easy of execution. The antidotes for 
the different poisons it is of vital importance for every physi- 
cian to know, and it shall now be our aim to point out the 
chemical antidotes for the different poisons to the best of our 
ability. The following table, taken for the most part from 
Taylor on Poisons, pp. 75-76, gives a tolerably full list of the 
poisons and their antidotes, so far as those antidotes act 
chemically. With the physiological antidotes of the poisons 
we have nothing to do: 
POISONS ANT 11 >0T ES. 
Acids.—The antidotes for acids are the alkalies, generally ; 
magnesia, carbonate of lime, chalk, carbonate of soda or of 
potash. For oxalic and tartaric acids carbonate of lime is the 
best antidote. 52 
Value of Chemistry to the Medical Practitioner. 
Binoxalate and Bitartrate of Potash.—The carbonates 
of lime and soda or sulphate of lime dissolved in water. 
Alkalies.—Yinegar, lemon juice, citric acid and oil. 
Baryta and-its Soluble Salts.—Sulphates of soda, potash, 
magnesia or lime. 
Alum.—Carbonate of soda, or sesqui-carbonate of ammo- 
nia. 
Arsenic.—Hydrated sesquioxide of iron, hydrated mag- 
nesia. 
Mercury.—Albumen in some form : the white of egg. 
Lead.—The alkaline sulphates, dilute sulphuric acid. 
Carbonate Lead.—Sulphate of magnesia and vinegar di- 
luted. First forms acetate of lead which is neutralized by 
the sulphate magnesia. 
Copper.—Albumen from eggs, milk, gluten or flour stirred 
in water. 
Tartarized Antimony.—Tannic acid, or substances con- 
taining it, and magnesia. 
Chloride of Antimony.—Carbonate of soda and magne- 
sia. 
Tin and Zinc.—Milk, carbonate of soda, and magnesia.— 
{Taylor). Orfila says that tin is not poisonous.—(Mialhe, 
p. 368). 
Sulphate Iron.—Carbonate of soda and sesqui-carbonate 
of ammonia. 
Nitrate of Silver.—Chloride of sodium or common salt. 
Forms by double decomposition nitrate of soda and chloride 
of silver. 
Iodine has been proposed as an antidote to strychnine, 
but I know of no case in which it has been used. It is incom- 
patible with the strychnine and quinine, and probably other 
vegetable alkaloids, and for this reason was proposed as an 
antidote to strychnine. Value of Chemistry to the Medical Practitioner. 
53 
x~xr. 
The subject of chemical incompatibles is according to Par- 
rish (Practical Pharmacy, jp. 456) too much of a stumbling 
block to the student. "We think he underrates the import- 
ance of the subject. It is only necessary for one to inquire 
of a druggist who is in the habit of filling prescriptions, to 
learn how frequently mistakes of this character occur. For 
example, a prescription, which is not very unusual, is one 
composed of oxalate of cerium and lime water. The lime 
water decomposes the oxalate of cerium and oxalate of lime 
is formed, which, as we have seen, constitutes one form of cal- 
culus. It is true that it is very insoluble but, we do not think 
any thinking man in the present state of our knowledge 
would like to administer oxalate of lime. On the other hand 
physicians are sometimes prevented from combining medicines 
which are perfectly compatible they think them in- 
compatible. A few days ago we heard a gentleman wish 
that he could combine bromide of sodium and chloral hy- 
drate in the same prescription, but die said lie was confident 
they would decompose each other. We knew nothing to the 
contrary, but on general principles did not think they were in- 
compatible. A trial proved them to be perfectly compatible 
chemically. 
I have determined, therefore, to devote some space to the 
consideration of this subject, although it is one about which, 
more than any other, I feel my own great ignorance. To 
give a complete list of incompatibles or even the action 
upon each other of the very various ingredients of the pre- 
scriptions of some physicians,who seem to think that “there 
is safety in numbers,” would require a volume as large as 
Webster’s dictionary (unabridged.) 
In the following very incomplete list taken for the most 
part from Dunglison's “ Therapeutics and Materia Medica,” 
I shall endeavor to give the most prominent incompatibles : 
CHEMICAL JHCOMPATIBLES. 54 
Value of Chemistry to the Medical Practitioner. 
Acidura Arseniosum, Arsenious Acid.—Bark, decoction of. Copper, sul- 
phate of. Lime water. Silver, nitrate of. Potassium, iodide of. Potassa, 
sulphohydrate of. 
Acidum Ilydrocyanicum, Hydrocyanic Acid.—Acids, mineral. Antimony, 
oxides of. Chlorine. Iron, salts of. Mercury, oxides of. Oxides generally. 
Silver, nitrate of. Sulphurets. 
Acidum Muriaticum, Muriatic Acid.—Alkalies. Carbonates. Earths. 
Lead, acetate of. Oxides. Potassa, sulphate of. Potassa, tartrate of. Silver, 
nitrate of. 
Acidum Nitricum, Nitric Acid.—Alcohol. Alkalies. Carbonates. Earths. 
Ii-od, protosulphate of. Lead, acetate of. Oils, essential. Oxides. Potassa* 
acete of. Sulphurets. Zinc, sulphate of. • 
Acidum Oxalicum, Oxalic Acid.—Lime, salts of. 
Acidum Sulphuricum, Sulphuric Acid.—Alcohol. Barium, chloride of. 
Calcium, chloride of. Carbonates. Clilorohydrates. Nitrates. Oils, essen- 
tial. Organic substances. Oxides. Sulphohydrates. Vegetable astringent 
infusions. 
Acidum Tartaricum, Tartaric Acid.—Alkalies. Carbonates, alkaline. 
Carbonates, earthy. Earths. Lead, salts of. Lime, salts of. Lime water, 
Mercury, salts of. Potassa, salts of. Vegetable astringents. 
Alumen, Alum.—Alkalies. Alkaline salts. Ammonia, carbonate of. 
Ammonia, chlorohydrate of. Galls. Kino. Lead, acetate of. Lime water. 
Magnesia, carbonate of. Mercury, salts of. Potassa, tartrate of 
Ammonhe Acetatis Liquor, Solution of Acetate of Ammonia.—Acids. 
Alkalies. Alum. Copper, sulphate of. Iron, sulphate of. Lime water. 
Lead, acetate of. Magnesia, sulphate of. Mercury, bichloride of. Silver, 
nitrate of. Zinc, sulphate of. 
Ammonite Liquor, Solution of Ammonia.—Acids. Alum, Salts, metallic. 
Ammonias Carbonas, Carbonate of Ammonia.—Acids. Alkalies, fixed. 
Alum. Carbonates, alkaline. Iron, sulphate of. Lead, acetate of. Lime. 
Lime, chloride of. Magnesia. Magnesia, sulphate of. Mereury, acetate of. 
Mercury, bichloride of. Mercury, protochloride of. Potassa, bitartrate of. 
Salts, acidulous. Zinc, sulphate of. 
Ammonite Murias, Muriate of Ammonia.—Acid, sulphuric. Acid, nitric. 
Alkalies, fixed. Carbonates, alkaline. Iron, sulphate oe. Lead, acetate of. 
Lime. Magnesia. Magnesia, sulphate of. Potassa. Potassa, carbonate of. 
Salts, metallic. Silver, nitrate of. Zinc, sulphate of. 
Antimonii et Potasste Tartras, Tartrate of Antimony and Potassa.— 
Acids, mineral. Alkalies. Carbonates, alkaline. Decoctions, bitter. Earths. 
Sulphohydrates. Infusions, bitter. Metals. Soaps. 
Argenti Nitras, Nitiiame of Silver.—Acid, arsenious. Acid, chloroby- 
dric and Salts. Acid, sulphuric and salt3. Acid, tartaric and salts. Alkalies, 
fixed. Earths, alkaline. Sulphohydrates. Soaps. Vegetable astringent in- 
fusious. Water, common. 
Calcis Liquor, LJme Water.—Acids. Borates. Citrates. Infusions, 
astringent, Salts, alkaline. Salts, metallic. Sulphur. Tartrates. Tinctures. 
Oxalates. Value of Chemistry to the Medical Practitioner. 
55 
Capri Sulphas, Sulphate of Copper.—Alkalies. Ammonia, acetate of. 
Calcium, chloride of. Carbonates, alkaline. Lead, acetate of. Lead, tria- 
cetate of. Lime water. Mercury, bichloride of. Potassa, tartrate of. Silver, 
nitrate of. Soda, biborate of. Vegetable astringent infusions. Vegetable as- 
tringent tinctures. 
Ferri Chloridi Tinctura, Tincture of Chloride of Iron.—Alkalies. Car- 
bonates, alkaline. Mucilage. Vegetable astringent infusions. 
Ferri et Potassae Tartras, Tartrate of Iron and Potassa.—Acids Lime 
water. Potassa, sulphohydrate of. Vegetable astringents infusions. 
Ferri Sulphas, Sulphate of Iron.—Alkalies. Ammonia, acetate of. Am- 
monia, chlorohydrate of. Carbonates, alkaline. Earths. Lead, acetate of. 
Lead, triacetate of. Potassa, nitrate of. Potasse and soda, tartrate of. Salts, 
with base forming insoluble sulphates. Silver, nitrate of. Soda. Soda, bib- 
orate of. Vegetable astringent infusions. 
Ilydrargyri Chloridum Corrosivum, Corrosive Chloride of Mercury.— 
Almond mixture. Alkalies, fixed. Ammonia. Antimony and potassa, tar- 
trate of. Bismuth. Carbonates, alkaline. Copper. Iron. Lead. Lead, 
acetate of. Lime water. Mercury. Oils, volatile. Potassium, sulphuret of. 
Silver, nitrate of. Soap. Sulphur. Zinc. Chamomile, infusions of. Cin- 
chona, infusions of. Columbo, infusions of. Horseradish, infusions of. Oak 
bark, infusions of. Senna, infusions of. Simaruba, infusions of. Tea, infu- 
sions of. 
Hydrargyi Chloridum Mite, Mild Chloride of Mercuryu—Acid, nitric. 
Alkalies. Antimony, golden sulphuret of. Carbonates, alkaline. Chlorine. 
Copper. Iron. Lead. Liine water. Potassium, sulphuret of. Soaps. 
Liquor Arsenici et Ilydrargyri, Soluion of Arsenic and Mercury.—Laud- 
num. Sulphate, muriate and acetate of Morphia. 
Lupulina., Lupuline.—Iron. Mercury, salts of. Platinum, salts of. Tin, 
salts of. 
Magnesia; Carbonas, Carbonate of Magnesia.—Asids.' Alkalies. Alum. 
Copper, sulphate of. Iron, sulphate of. Lead, acetate 'of. Mercury, bich- 
loride of. Potassa, bitartrate of. Salts, acidulous. Salts, neutral. Silver, 
nitrate of. Zinc, sulphate of. 
Magneaiae Sulphas, Sulphate of Magnesia.—Alkalies, fixed. Ammonia, 
muriate of. Barium, chloride of. Calcium, chloride of. Carbonates, alkaline. 
Lead, acetates of. Silver, nitrate of. 
Morphia, Morphia.—Oxides, metallic. 
Morphia, Salts of.—Alkalies. Carbonates, alkaline. Decoctions of vege- 
table astringents. Infusions of vegetable astringents. Lime. Magnesia. 
Silver, nitrate of. 
Opium (solid), Opium —Alkalies. Cincnona. Galls. Lead, acetate of. 
Mercury, bichloride of. 
Plumbi Acetas, Acetate of Lead.—Acids. Alkalies. Alum. Ammonia, 
solution of acetate of. Antimony and potassa, tartrate of. Carbonates, alka- 
line. Earths, alkaline. Cholorohydrates. Iron, ammoniated. Iron and po- 
tassa, tartrate of. Soaps. Seda, biborate of. Sulphates. Sulphurets. Water, 
common. 56 
Value of Chemistry to the Medical Practitioner. 
Plumbi Subacetatis Liquor, Solution of Subacetate of Lead.—Alkalies. 
Carbonates, alkaline. Mucilage. Soap liniment. Sulphates, alkaline. Sul- 
phurets of alkaline metals. 
Potass® Acetas, Acetate of Potassa.—Fruits, acid. Acid, mineral. 
Tamarinds. Salts, acid. Salts, alkaline. Salts, metallic. 
Potass® Arsentis Liquor, Solution of Arsenite of Potassa.—Cinchona, 
infusion of. Copper, salts of. Lime water. Potassa, sulpholiydrate of. Silver, 
nitrate of. 
Potass® Carbonas, Carbonate of Potassa.—See Potass® bicarbonas. 
Potassas Bicarbonas, Bicarbonate of Potassa.—Acids. Alum. Ammonia, 
acetate of. Ammonia, carbonate of. Ammonia, muriate of. Antimony and 
potassa, tartrate of. Copper, acetate of. Copper, sulphate of. Iron, chloride 
of. Iron and potassa, tartrate of. Iron, sulphate of. Lead, acetate of. Lime 
water. Magnesia, sulphate of. Mercury, bichloride of. Mercury, protoch- 
loride of. Silver, nitrate of. Salts, acidulus. Soda, biborate of. Zince, sul- 
phate of. 
Potass® Nitras, Nitrate of Potassa —Acid, sulphuric. Alum. Copper, 
sulphate of. Iron, sulphate of. Magnesia, sulphate of. Soda, sulphate of. 
Zinc, sulphate of. 
Potass® Sulphas, Sulphate of Potassa.—Acid, chlorohydric. Acid, ni- 
tric. Lead, acetate of. Lime and compounds. Mercury, bichloride of. Silver, 
nitrate of. 
Posassa® Tartras, Tartrate of Potassa.—Acids. Barium, chloride of. 
Lead, acetates of. Lime. Magnesia, Salts, acidulous. Silver, nitrate of. 
Tamarinds. Vegetables, acid. 
Potass® Bitartras, Bitartrate of Potassa.—Acids, mineral. Alkalies. 
Earths, alkaline. 
Quini® Sulphas, Sulphate of Quinia.—Alkalies. Earths, alkaline. In- 
fusion of orange-peel, compound. Infusion of Roses. Solutions, astringent. 
Tincture of cinchona. Iodine. 
Sod® Boras, Borate of Soda.—Acids. Ammonia, chlorohydrate of. 
Ammonia, sulphate of. Chlorohydrates, earthy. Potassa. Sulphates, earthy. 
Sod® Carbcnas, Carbonate of Soda.—See Carbonate of Potash. 
Sod® et Potass® Tartras, Tartrate of Soda and Potassa.—Acids. Am. 
monia, muriate of. Baryta, salts of. Lead, acetate of. Lime, salts of. Mag- 
nesia, sulphate of. Potassa, sulphate of. Salts, acidulous. Soda, sulphate of. 
Tamarinds. 
Sod® Sulphas, Sulphate of Soda —Acid, chlorohydric. Acid, nitric. 
Acid, sulphuric. Barium, chloride of. Lime. Magnesia. 
Sod® Sulphas, Sulphate of Soda.—See Magnesia Sulphas. 
Zinci Sulphas, Supiiate of Zinc.—Alkalies. Earths. Milk. Sulphohy- 
drate3. Vegetable astringent infusions. 
In this essay, which I am now about to bring to an end, 
it lias been my aim as far as possible to confine myself to 
subjects which were well understood, and when I have given Value of Chemistry to the Medical Practitioner. 
57 
theories which had not been proven, I have generally stated 
that they were only theories. I have endeavored, too, to con- 
iine myself to those subjects a knowledge of which are of use 
to the physician in his daily life and practice; and when I have 
ventured to touch upon subjects which are as yet of purely 
scientific interest, it has been from the conviction that further 
investigations would show their practical import. The vast 
strides which organic chemistry is now making will undoubt- 
edly throw great light on many points in medicine which are 
now very obscure. 
There has been a tendency, we think, on the part of 
many of our ablest physicians to neglect chemistry, from an 
idea that viewing the changes which occur in disease as 
chemical changes tended to materialism ; and whole volumes 
have been written on the vital theory of disease. We are 
far from denying that there are vital changes as well as chem- 
ical changes in disease. In the present state of pathology 
the former are probably more prominent and important than 
the latter; but we can see nothing in the chemical theory 
which militates against the Bible. Tyndall himself is no 
firmer believer in an universal “ Reign of Law,” than the 
writer of this article; but until he can prove that there are 
no more laws undiscovered, and until he can foretell the effect 
produced by every possible combination, of known laws, I 
shall still believe that I have “ a reason for the faith that is 
in me.” Then— 
“ Let knowledge grow from more to more, 
But more of reverence in us dwell. 
That mind and soul according well, 
May make one music as before,— 
But vaster.”