CHEMICAL, MEDICAL AND DIETICAL PROPERTIES. 219 



the medical action of the tea infusion upon the system 

 is the result of the several effects of this alkaloid formed 

 by combination of the theine, tannin, volatile oil, and the 

 hot water. Of these elements theine probably plays the 

 most important part, and like all other potent alkaloids 

 theine is a powerful modifier of the nerve functions, 

 increasing the action of the skin and cooling the body 

 by lessening the force of the circulation, but does not 

 cause any congestion of the mucuous membrane, partic- 

 ularly in that of the bowels. In answer to the question 

 whether theine produces nervousness and wakefulness, 

 reliable authorities answer : No ! But that, on the con- 

 trary, the effect of theine upon the human system is a 

 calming and soothing one, producing a sense of repose 

 and supplying to the body that which is lost by fatigue. 

 The experiments made with tea on a number of 

 animals for the purpose of ascertaining its effects on the 

 nervous and muscular apparatus give varying results, the 

 most important being that of lessening the amount of 

 nitrogenous excreta, notably that of the urine, which 

 means to diminish the rate at which nitrogenous sub- 

 stances are oxydized within the body, such action being 

 probably due to the volatile oil, as Lehman found the 

 same oil in roasted coffee to produce the same action in 

 his experiments. There being a substance in the flesh 

 or muscles of all animals known as kreatine, the chemi- 

 cal properties of which are analogous to those of theine, 

 and it is now generally accepted that these substances 

 are most agreeable to the human system as food which 

 most nearly resemble the compound that form the tissues 

 and muscles of the body, while those act as poison 

 whose composition is most different from that of the 

 tissues and muscles on which the life of the body 

 depends. Scientists who have made this subject a 



