252 CHEMICAL CONSTITUENTS. 



alters it to a stronger base, termed Cafifeidine, but when 

 boiled with an excess of nitric acid and evaporated at a 

 gentle heat gives it a reddish color resembling that 

 obtained from minoxide; the addition of a little ammonia 

 making it again quite characteristic. Administered in 

 strong doses it causes trembling and a kind of intoxica- 

 tion not unlike that resulting from alcoholic stimulants, 

 but diminishes the work of organic tissue at the same 

 time. 



Caffeone. — Besides Caffeine coffee contains a volatile 

 or essential oil chemically termed Caffeone which, accord- 

 ing to some authorities, is not present in the raw bean, 

 but is the result of an essential change produced in the 

 coffee by the roasting process. It is to this subtle and 

 fugitive principle, however, that roasted coffee owes its 

 peculiar and fragrant aroma, an odor possessed by no 

 other known substance. When chemically separated by 

 ether from the coffee it presents the appearance and con- 

 sistency of cocoa- butter, which in roasting permeates the 

 entire bean, but if the heat be too intense or the roasting 

 prolonged beyond the proper time, it is entirely dissipated 

 and lost, the result being to seriously injure the coffee. 

 And although coffee forms part of the daily food of more 

 than half the nations of the world, we are still uncertain 

 of the chemical nature, composition and effects of these 

 products of roasted coffee, and particularly of this " oil of 

 coffee," one of the most important characteristic con- 

 stituents of the bean. The existence of this coffee oil 

 makes itself known in a striking manner by its roasting; 

 being forced out of the bean by the intense heat, it is 

 partially volatilized, and together with the other products 

 of the roasting, produces the characteristic effects and 

 aroma of roasted coffee. In very strong black coffee it is 

 found in oil-like drops floating on the surface, the amount 



