O'SHEA — ASPECTS OF MENTAL ECONOMY. 



109 



Analyses of tea, coffee, and cocoa. 



Composition of black tea : 

 Water 



Albuminoids 

 Theine 

 Tannin 



Chlorophyll and resin 

 Essential oil 

 Minor extractives 

 Cellulose, etc 

 Mineral matter 



Composition of roasted coffee 

 Water 



Albuminoids 

 Theine (Caffeine.) 

 Fat or oil 

 Tannin 



Minor extractives 

 Cellulose, etc 

 Mineral matter 



Composition of cocoa : 

 Water 

 Albuminoids 



Fat 



Theobromine 



Cacao-red 



Tannin 



Gum, etc 



Cellulose and insoluble matter 



Mineral matter 



People do not commonly prize tea and coffee, however, for 

 their nutritive worth, but only for the stimulating effect which 

 they exert upon the nervous system. Smith 1 has carefully 

 studied their action upon the vital functions and it will be well 



And first regarding tea : 



to give the results of his experiments 



"1. As to the Carbonic Acid Evolved in Respiration. 



"1. One hundred grains of the finest black tea gave a maximum 

 increase of 0.87 grain and 1.72 grain per minute in 50 and 71 minutes 

 on two persons. 



"2. Fifty grains gave to four persons maxima of increase of 1.08, 

 1.38, 2.58, 1.6, 2.0, and 0.69 grains per minute, under different experi- 

 ments. 



"3. One hundred grains of the finest green tea, drank when cold, gave 

 maxima of increase of 0.9, 2.58, and 0.64 grains per minute on three 

 persons. 



"4. Twenty-five grains of green tea, drank when cold, and after hav- 



!Op. cit., pp. 347-350. 



