SECT. XIII. OILS. 



SUBSECTION IX. 



General Remarks. From the experiments that Compost 

 have been made upon vegetable acids it appears that vegetable 

 all of them contain carbon, oxygene, and hydrogene, acids> 

 in one proportion or other ; and that the prussic acid 

 contains also a portion of nitrogene. The gallic acid 

 contains more of carbon than any other vegetable 

 acid, and the oxalic more of oxygene. 



SECTION XIII. 



Oils. 



VEGETABLE OILS are of two kinds, the fixed and Their dm- 

 the volatile. The former are not suddenly affected 81< 

 by the application of heat ; the latter are very in- 

 flammable. 



SUBSECTION I. 



Fixed Oils. Fixed oils are but seldom found, ex- in what 

 cept in the seeds of plants, and chiefly in such as are 

 dicotyledonous. They are found also, though rarely, 

 in the pulp of fleshy fruits, as in that of the Olive, 

 which yields the most abundant and valuable species 

 of all fixed oils. But dicotyledonous seeds which 

 .contain oil, contain also, at the same time, a quantity 

 of mucilage and fecula, and form when bruised in 

 water a mild and milky fluid known by the name of 



4 



