MICrvO-CHEMICAL EXAMINATION OF EXTRACT OF FLESH. 1*J9 
have a few remarks on these in another portion of the paper, chiefly in 
connection with statements made by one of ns at th^last meeting of the 
Pharmaceutical Conference. 
In making these observations it is our object not to intrude commercial or 
personal considerations, nor, further than is necessary with a scientific end, 
to institute comparisons between the various manufacturers. The names of 
the two British houses which we have introduced have been selected as pro¬ 
ducing samples of excellence,—a number of other specimens of home manu¬ 
facture which have come under our notice, of varying degrees of goodness or 
badness being omitted, inasmuch as no good end would be answered by criti¬ 
cism upon them. 
We may now proceed to consider the chemical constituents of flesh extract, 
and these may be classed under two heads, inorganic and organic. The in¬ 
organic matter consists of alkaline (and earthy ?) phosphates and chlorides, 
principally phosphate of potash and chloride of potassium. If phosphate of 
magnesia be present as stated by some authors, we believe it to exist in ex¬ 
tremely small proportions. It is quite possible, that ammonia may occur 
as the base of a phosphoric acid compound. The organic portions of the 
extract are kreatine, possibly kreatinine, and the colloidal matter consisting 
of gelatine and extractive. We have used the term “ gelatine” for want of 
a better word, to include, in a general sense, the viscid, gluey portions of the 
uncrystallizable extractive which are precipitated by tannic acid and infusion 
of galls. Theoretically, true gelatine should not exist in extract of flesh, and 
it is not unlikely that the gelatinous matter consists chiefly or in part of 
chondrine, a closely allied substance, giving very similar reactions, which is 
found largely in cartilage. The remaining uncrystallizable matter, alluded 
to as “ extractive,” is probably in part derived from the decomposition of the 
gelatinous principles by the heat employed in the preparation of the extract. 
This idea is confirmed by the fact that one of our samples, of inferior quality 
and containing a large proportion of colloids, gave only a small precipitate 
with the tannic acid test. Lactic acid probably exists in some proportion in 
combination with one or other of the bases referred to. We shall confine 
our attention to those of the salts and principles we have above named whose 
presence may be readily recognized and may be regarded as essential to well- 
made extract, especially to phosphate of potash, chloride of potassium, kreatine, 
and colloids. It is necessary to bear in mind the distinction between “ juice 
of flesh,” the analysis of which is given in many chemical works, and the 
extract now under consideration. The former is merely the fluid portion 
pressed out of the muscular tissues ; the latter includes all the substances that 
hot w ater will dissolve out, in the condition in which they are left after eva¬ 
poration, and altered as they may be by the application of continued heat. 
Acid orthophosphate of potash (tribasic) POg ^ 9^0 is readily soluble 
in water, insoluble in alcohol, the crystals taking the form of prisms with 
obliquely wedge-shaped ends, or of some modification of that form. It is a 
beautiful object under the microscope, and most brilliant when viewed by 
polarized light. Figure 1 of our plate represents orthophosphate of potash 
crystallized from its aqueous solution. Fig. 2. The same, from a solution to 
which a small proportion of vegetable extractive had been added. 
Chloride of potassium (KCl) exists in considerable quantities in extractum 
carnis, but from its extreme solubility in water is never conspicuous in micro¬ 
scopic preparations of the extract itself. 
Our Fig. 2 a represents the crystallization from an aqueous solution. 
Fig. 2 h, crystals from alcohol. In order to observe the influence of extrac- 
