ON ANIMAL MATTER. 81 



conjunction. of sexes ; and others are reproduced when cut in 

 pieces, like the roots of plants. 



All animals are fed on vegetables, either directly or by the 

 intervention of other animals. 



As the animal, then, is derived from the vegetable matter, 

 we find, accordingly, that the former is capable of being re- 

 solved into the same principle as those of the latter. Thus, 

 by repeated distillations, we obtain from animal substances 

 water, oil, air, and easily destructible salt and charcoal. These 

 secondary principles are, by further processes, at length reso- 

 luble into the same proximate principles which we find in 

 vegetables, viz., air, earth, and water, and the principle of 

 inflammability. 



But though the principles of vegetable and animal substan- 

 ces are fundamentally the same, yet these principles are com- 

 bined in a different manner. It is exceeding rare that animal 

 substances are capable of the vinous or acetous fermentation; 

 and the putrefactive, into which they run remarkably fast, is 

 also different in some particulars from the putrefaction of 

 vegetables. The smell is much more offensive in the putre- 

 faction of animal than of vegetable substances. The putre- 

 faction of urine, is, indeed, accompanied with a peculiar fetor, 

 by no means so intolerable as that of other animal matters ; 

 this is probably owing to the pungency of the volatile 

 alkali, and also to the urine containing less inflammatory mat- 

 ter than the blood and other fluids. When analyzed by a 

 destructive heat, animals afford products very different from 

 those of vegetables ; the oil has a particular and much more 

 fetid odor, and the volatile salt, instead of being an acid, 

 found as it is in most vegetables, is found in animals to be a 

 volatile alkali. 



Chemists have spoken of an acid procurable from animal 

 substances, and, indeed, certain parts of animal bodies are 

 found to yield a salt of this kind ; but it by no means is the 

 case with animal substances in general. In some animals an 

 acid exists uncombined and ready formed in their bodies. 

 This is particularly manifest in some insects, especially ants, 



