120 ALIMENTATIOlSr. 



the peculiar effects upon the nervous system which are 

 characteristic of both tea and coffee, there is good reason 

 to suppose that they are also identical in their physiological 

 effects. Theine (or caffeine) exists in greater proportion in 

 tea than in coffee ; but, as a rule, much more soluble matter 

 is employed in the preparation of coffee, which may account 

 for its more marked effects upon the system. 



Green tea, especially in those unaccustomed to its use, 

 frequently produces nervous tremor, wakefulness, and dis- 

 turbed sleep when sleep can be obtained palpitations, and 

 other disturbances usually termed nervous. In some persons 

 these unpleasant effects may be overcome by habit; and 

 many constantly use a mixture of equal parts of black and 

 green tea with no unpleasant effects. The peculiar effects 

 of green tea are attributed to the volatile oil, which it con- 

 tains in great abundance. 1 



Tea is prepared for drinking by rapidly making an infu- 

 sion of the leaves with hot water. The aroma is nearly 

 destroyed by boiling. The proportion generally used is about 

 three hundred grains of tea to a quart of water. The tea is 

 first covered with boiling water, and allowed to steep, or 

 " draw," for from ten to fifteen minutes, in a warm place ; 

 and boiling water is then added in the quantity desired. 

 Green tea, treated in this way, yields about twenty per cent, 

 of soluble matters, and black tea, about twenty-three per 

 cent. 8 



Chocolate. 



Chocolate is made from the seeds of the cocoa-tree, roast- 

 ed, deprived of their husks, and ground with warm rollers into 

 a pasty mass with sugar, flavoring substances being sometimes 



1 It is a question still undecided whether green tea be actually a distinct 

 variety, or whether it differ from black only in the mode of curing. The leaves 

 of green tea are smaller and younger when gathered, and are cured more rapid- 

 ly than black tea. 



2 PA YEN, op. tit., p. 428. 



