182 PHYSIOLOGY. 



oil to cover the acrimony of the animal fluid, it' must prove at 

 the same time that this admits of an intimate mixture with the 

 oil. 



" As the want of food is a principal occasion of the absorp- 

 tion mentioned, this affords a proof that such absorption is a 

 means of supplying aliment, or at least of covering the acrimony 

 which upon the want of aliment is ready to take place. Upon 

 either supposition, it affords a proof that oil unites very inti- 

 mately with the other parts of the blood : and, upon the whole, 

 there can be little doubt that oil taken in, either in its separate 

 or united state, is a part, and a considerable part, of the human 

 aliment." M. M. 



CCXIII. It is the saccharine matter, and especially this 

 when blended with oily matter in different proportion, that 

 makes the greatest part of the common matter of vegetables, 

 and is the chief part of the vegetable aliment of animals. It is 

 this, therefore, that we have especially to consider here ; and, 

 as it lies in vegetables, it is different from the most part of ani- 

 mal matters in the following respects. 



It is readily susceptible of a vinous and acetous fermentation, 

 and spontaneously enters into the one or the other of these; and, 

 without undergoing more or less of these, it perhaps never en- 

 ters into a putrefactive fermentation. 



The same matter treated by distillation, without addition, 

 gives out always, in the first part of the distillation, an acid, 

 and only afterwards a volatile alkali in small proportion. 



The same vegetable matter, treated by calcination, leaves 

 ashes, which contain a fixed alkali, and an earth, that is, or may 

 be converted into a quick-lime. 



CCXIV. In all these respects, the common matter of ani- 

 mals is considerably different. 



This enters spontaneously into a putrefactive fermentation, 

 and that without passing through the vinous or acetous : at 

 least these are not to be distinctly perceived. 



The same animal matter treated by distillation, gives out al- 

 ways, in the first part of the distillation, a volatile alkali in large 

 proportion, and only afterwards, by a great force of fire, it gives 

 out an acid. 



