162 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[August 81,1872. 
wliich the distilled water had dissolved, and with 
which quantity the pepsin had been in contact before 
the acid was added, was sufficient to modify the 
pepsin and destroy its digestive action on fresh 
coagulated albumen. In 13, the carbonates of the 
well water had caused the same result. In D, the 
carbonates were destroyed by the addition of acid 
before the pepsin was added, and therefore the albu¬ 
men was easily dissolved. Such proofs, I think, 
must necessarily convince the most sceptical. 
The physician might wish for a combination of 
pepsin and bismuth in the liquid state, but another 
question is, can such a combination be made, or can 
it exist? Those that manufactured the elixir of 
pepsin and bismuth (and strychnine), were satisfied 
to know that they used pepsin in its preparation, but 
whether it was in it or in an active form, never 
troubled them, as they never tested for it. They 
could conscientiously put their label on the bottle, 
and maintain that they used pepsin in its prepara¬ 
tion. The physician prescribed it in good faith, 
because he had confidence in the firm who made it, 
and in the name by which the preparation was 
designated. 
Having tested several elixirs of pepsin and bismuth 
that I was able to obtain I found that even after the 
addition of hydrochloric acid not the least quantity 
of albumen was dissolved. 
Thinking that an acidulated bismuth solution 
might, in combination with pepsin, prove more effi¬ 
cacious, containing the pepsin in its active form, my 
first aim was to find a bismuth salt for that purpose. 
Crystallized ternitrate of bismuth dissolves in gly¬ 
cerine, which solution can be diluted with a con¬ 
siderable quantity of water before the subnitrate is 
precipitated. This salt I dropped from the list, as 
the solution is too acid, and the taste too styptic. 
Freshly precipitated subnitrate of bismuth, prepared 
with one part of crystallized ternitrate with 40 
parts of water was put on a filter, and when entirely 
drained added to glycerine, in which it dissolves, 
forming a clear solution, but on the addition of water 
the clear solution becomes milky after some time. 
I now tried the action of acids on ammonio-citrate 
of bismuth. For that purpose I made two solutions 
of ammonio-citrate of bismuth of the same strength, 
with the difference that the one solution was made 
with water alone, and the other with a mixture of 
glycerine and water. To these solutions were now 
added different acids, and the following results ob¬ 
tained : Mineral acids gave in both solutions im¬ 
mediately a precipitate. By the addition of organic 
acids, such as acetic, lactic and citric, both solu¬ 
tions kept clear, but after a lapse of several hours 
the pure water solutions became milky, and by 
longer standing deposited a white precipitate, while 
in the solutions containing glycerine an opalescence 
did not show itself before twenty-four hours. 
Judging that a small quantity of organic acid, 
sufficient to dissolve the pepsin, would not give even 
an opalescence in a solution of ammonio-citrate of 
bismuth containing glycerine, I thought that a gly- 
cerole could be made containing pepsin as well as 
bismuth, etc.; but by mixing the pepsin solution 
with the solution of the bismuth salt, the pepsin was 
precipitated in the same characteristic form as it is 
precipitated from its solutions by chloride of sodium. 
Having at first intended to make the glycerole 
contain in the pint 128 grains ammonio-citrate of 
bismuth, 250 grains of saccharated pepsin (respec¬ 
tively 1 and 2 grains to the fluid drachm), 1 fluid 
drachm of lactic acid, 8 fluid ounces glycerine, and 
8 ounces of water, I thought that by making it only 
half as strong in bismuth and pepsin it might 
answer, but tlie pepsin was in this instance also 
precipitated. The ingredients were put together in 
four different ways, but in all with the same result. 
This negative result proves clearly that the pepsin 
is precipitated from its solution by the bismuth salt, 
and as I have proven in my essay (Feb. 1872), that 
a watery solution of pepsin is precipitated by chloride 
of sodium in the same way as an acidulated one, we 
must infer that the bismuth salt acts in the same 
manner, and that therefore the elixir of pepsin and 
bismuth, as it was made, cannot contain any pepsin. 
Abstracting, therefore, from the alcohol, and not 
speaking of the neutral or alkaline solution, the 
elixir of pepsin and bismuth is an incongruity, and 
when patients have derived any benefit from it, it 
has been from the bismuth it contained, and the 
stimulating effect of the spirits, but surely not from 
the pepsin, as it does not contain any pepsin. — Amer. 
Journ. Pharmacy. 
ORGANIC CHEMISTRY AND THERAPEUTICS.* 
BY A. W. HOFMANN. 
(Continued from p. 14 6.J 
There is no need to establish an artificial line of de¬ 
marcation. The group of hydrocarbons and their de¬ 
rivatives are clearly distinguished from the rest of the 
chemical edifice. Born from the union of two powerful 
radicals, carbon and hydrogen, these bodies can, under 
the influence of a small number of elements, give birth 
to innumerable compounds, which, spite of the infinite 
variety of their properties, bear all of them the mark of 
one indubitable parent; they are the primary matter 
from which plants and animals are formed. The group 
unites an assemblage of properties such as are not 
present in any other class of combinations, and which, 
if they do not permit the drawing of a well-defined line 
of demarcation, are sufficient to justify the consideration 
of these bodies as a distinct group. 
But what is the influence which the researches in the 
field so defined have exercised upon the development 
of therapeutics ? The chief features only of the principal 
services rendered by chemistry to therapeutics can here 
be indicated. In his early studies upon the substance 
of plants and animals the chemist is led to use analytical 
methods, and at starting it is only by analytical facts 
that therapeutics profits by the progress of chemistry. 
The physician is enabled for the first time to recognize 
the active principles of a series of medicaments long em¬ 
ployed with success, and in many cases these active princi¬ 
ples when indicated by science have been substituted for 
the mixture, often so disagreeable, the properties of which 
have only been discovered by chance or by empiricism. 
An interesting example is found in the time when the 
study of organic chemistry first began to occupy the 
attention of chemists. The poisonous properties of bitter 
almonds (Amygdalus communis) had been indicated from 
antiquity. It was known also at the commencement of 
the eighteenth century that the leaves of the cherry- 
laurel (Primus lauro-cerasus) furnished an oil possessing 
poisonous properties, and in the closing years of the 
same century, cherry-laurel water was already em¬ 
ployed as a medicament. But at that time the nature 
of the active principle contained in bitter almonds and 
in cherry-laurel water was not yet suspected; and it 
was only at the commencement of the present century 
* Lecture delivered at the Medical Chirurarical Institute of 
Berlin. 
