ON PEPSINE. 307 
grammes. Each is placed in a separate vessel, with the addition of, first, 
25 grammes of water , secondly, acid, (lactic or other acid), a sufficient 
quantity to saturate 17 centigrammes of pure caustic potass (equivalent 
to the acidity of the gastric juice) ; thirdly, fibrine obtained from calves' 
blood, washed and strongly pressed in a cloth. The three vessels are 
then placed in a stove, and maintained at a uniform temperature of 45° 
C. for twelve hours. The sample in which the fibrine has been dissolved 
and converted into pure peptone (albuminose), not precipitable by nitric 
acid, is the normal and therapeutic dose of the pepsine. 
But as the weight of pepsine necessary to obtain this regular power 
varies incessantly, sometimes 25, sometimes 50, or 75 centigrammes, 
whichever it may be, at each operation, sufficient starch is added to 
make the weight one gramme, so that each gramme contains invariably 
a uniorm digestive power, the quantitity of starch alone varying. No 
physical or chemical characteristics distinguish active pepsine from that 
which is inert, nor from other nitrogeneous bodies more or less allied ; the 
only important quality being its digestive power, the test with fibrine 
is the only method of determining their value, all preparations, what- 
ever may be their aspect and chemical reactions, are not pepsine if they 
do not answer to it. The digestive characteristic consists in that pepsine, 
in twelve hours, dissolves fibrine, and converts it into peptone, not pre- 
cipitating from its solution by heat, alkalies or acids ; sometimes the 
dilute acids (hydrochloric, &c.) dissolve fibrine, causing it at first to 
swell enormously, which is characteristic of their action. Besides this, 
after twelve hours peptone is not formed ; as the liquid gives a large 
precipitate with nitric acid, this test is conclusive. The modes of 
administration proposed for pepsine are very numerous, but, in Corvisart's 
opinion, the pepsine in powder, the syrups, the elixirs, and wine answer 
every exigency. The most preferable forms are those that are most 
miscible with the food. Finally, besides the addition of codeia, nitrate 
of bismuth, strychnine, lactate of iron, and reduced iron (in small doses), 
which are without any injurious action on pepsine, many formulae have 
been proposed in which it is combined with a large number of other 
remedies ; but these preparations are better avoided. So the combina- 
tion of pepsine with alkalies or alkaline lactates is not physiological ; 
the alkalies very certainly produce good results in some dyspepsias, but 
they have an action very distinct from that of pepsine. We think that 
the alkaline salts and the gastric secretion may be mutually injurious 
when meeting in the stomach, especially when the stomach does not 
sufficiently renew the peptic fluid, for it is necessary to remember that 
the acidity is the essential ingredient in it, and it is therefore necessary 
to employ pepsine and the alkaline lactates separately. 
The solution remains perfectly transparent on the addition of four 
drops of nitric acid=pure pepsine. 
