114 
THE CODEX AND THE BRITISH PHARMACOPOEIA. 
and as the liquor comes through evaporate in wide but shallow vessels and at a 
variable temperature which does not exceed 45° Centigrade. 
Evaporate to dryness, and remove the product, which is in the condition of a 
firm paste and of a light brown or flaxen colour, with an acidulous taste and 
peculiar odour, but not in the least putrid or faded. This constitutes medicinal 
pepsine ; it dissolves forty times its weight of white, damp, but not wet blood 
fibrine ; to effect this, put into a small wide-mouth flask and not closed. 
Medicinal pepsine . . Twenty-five centigrammes 0 25 
Distilled water . . . Twenty-five grammes . . 25*00 
Concentrated lactic acid Forty centigrammes . . 0*40 
Damp fibrine .... Ten grammes . . . .10*00 
Place the flask in a hot-water stove, the temperature of w*hich does not exceed 
45° Centigrade, agitate several times. At the end of twelve hours, with the 
exception of a small greyish residue which fibrine always leaves, it will be dis¬ 
solved, and give to the liquid a semi-gelatinous consistence ; the liquid diluted 
with water and filtered does not become turbid by boiling ; it forms with tannin 
a precipitate which becomes coriaceous, and of a violet tint; alcohol gives an 
abundant white precipitate; nitric acid does not cause a precipitate without heat. 
A powder, more or less white, is met with in commerce, under the name of 
amylaceous acid pepsine, which is a mixture of medicinal pepsine, starch, and 
tartaric acid ; this is considered good, when a mixture of one gramme with 
twenty grammes of water and six grammes of damp fibrine, completely breaks 
up the fibrine and leads to the results before stated. 
This is the Codex account of pepsine and its preparation, and as such may 
be interesting to some readers, more especially as it is not mentioned in the 
P. B., although it might have been with quite as much reason as some of the 
more recent introductions. 
CHAPTER XXII. 
PYROGENIC PRODUCTS. 
Containing empyreumatic carbonate of ammonia or salt of hartshorn, volatile 
spirit of hartshorn, volatile oil of hartshorn, impure succinic acid, impure spirit 
of amber, volatile oil of amber, and impure succinate of ammonia. Looking at 
these as things of a past generation, I leave them simply recorded. 
CHAPTER XXIII. 
ARTIFICIAL MINERAL WATERS. 
There are nine of these artificial effervescing waters :—simple aerated water, 
acidulated saline, purgative saline, alkaline, ferruginous, sulphuretted, carbo¬ 
nated soda, magnesia, and purgative citro-magnesian lemonade, all of which 
may be safely left to the manufacturers of soda water and ginger beer. I know 
not what the French pharmacien may think of them, but, as a rule, they are 
most inconvenient and troublesome in a sick room. 
, CHAPTER XXIV. 
SIMPLE POWDERS. 
When the pharmaceutist is compelled to prepare the simple powders upon his 
own premises, the directions given in the Codex as to general rules and pre¬ 
cautions may be useful, but practice will soon be the best teacher as to the 
course to be observed in individual cases, and though it may and does seem 
unnecessary to give fifty-three individual cases, with the manner of reducing 
each to powder, besides a very long list of substances to be powdered as directed 
for other materials, it may not perhaps be useless to suggest to the English 
