152 SEVENTH REPORT—1837. 
solubility or insolubility of animal constituents in ether, water, 
and alcohol. 
1st. Those constituents of animal matter which are soluble in 
zther. 
Under this head we have the various fatty matters of the 
glands for consideration ; and, if this plan of analysis be extended 
to the products of disease in the various parts of the body, we 
shall find much matter of interest in the examination of this 
extract. The various modifications of fat, as occurring in dis- 
eased parts, and their secretions, have scarcely procured the 
attention they deserve from chemists. The peculiar nature of 
the fatty matters of the blood affords every facility for an easy 
passage into several varieties of that substance, and we find a 
series of very interesting changes in the secretions, excretions, 
morbid secretions, and growths of the human body. Thus cho- 
lesterine, which was once supposed to be the result of the 
secreting action of the liver, has been found in the fluid of hy- 
drocele, in ovarian tumours, &c. When the nature of the fatty 
matter of blood is known, it ceases to be a subject of surprise 
that cholesterine is so generally distributed, for the chemical 
reactions of the crystalline fat of the blood are almost identical 
with those procured from cholesterine, and probably but very 
slight means are needed for the reduction of one to the other. 
I may mention that cholesterine differs from the crystalline fatty 
matter of the blood in affording an ash having an alkaline reac- 
tion on test paper, whereas the crystalline fat yields an acid 
ash owing to the presence of phosphorus. In every other reac- 
tion, however, these substances are so much alike that it is 
almost impossible to distinguish them. I find that the alkaline 
ashes of cholesterine are in about the proportion of 2°5 per cent., 
containing an alkaline, carbonate,and muriate, traces of sulphate 
and phosphate, and also phosphate and carbonate of lime. 
The other forms of fatty matter met with in animal analysis 
are adipocere and common animal fat. I now come to the 
second division of our analysis, viz. : 
2nd. Those constituents of animal matter which are soluble 
in water only. 
In the analysis of the blood, the extractive procured as soluble 
in. water only consists apparently of albumen in combination 
with soda. The extractive procured by similar treatment of 
any of the glands of the body will require examination, and 
constitute an important part of our inquiry, as it probably may 
be of different nature in each gland. This extractive, as pro- 
cured from blood, is precipitable by acetic acid, the precipitate 
consisting of albumen in a gelatinous form. 
