FOODS, FOOD-STUFFS, AND FOOD-ADJUNCTS. 69 



administered to the patient. Many of these act 

 powerfully on the nervous system, generally as seda- 

 tives or narcotics ; but the action of those among 

 them which can be classed as food-adjuncts is often 

 modified by the presence of other substances, such, 

 for instance, as the stimulating essential oil and the 

 tannin which are present in tea. 



As has been before suggested, a botanical identifi- 

 cation is often nearly as important as a new discovery ; 

 and thus Fortune's identification of the Tea-plant 

 cultivated in China as TJiea viridis, L., was followed, 

 at a short interval, by its extensive introduction into 

 India, from which country we now derive much of our 

 most costly teas. In 1882 we imported more than 21 1 

 million pounds of tea, of which nearly 54 million 

 were from British India, over 165 million being for 

 home consumption. 



It is also a singular fact that most nations have 

 some non-alcoholic beverage, similar to tea, depending 

 for its value upon an alkaloid, and that these alkaloids, 

 though derived from different often widely different 

 plants and countries, are in several cases identical, 

 and in others most closely allied. Tea, coffee, kola, 

 guarana, mate, and holly leaves, all contain Caffeine, 

 or Theine, as it is sometimes called, whilst Theobro- 

 mine, the alkaloid of the Cacao (Theobroma Cacao, L.) 

 is very nearly related. 



COFFEE affords an instance of the ease with which 

 a trade may be destroyed. Its importation from 

 Ceylon fell from 921,506 cwt. in 1870 to 407,222 cwt. 

 in i88i,and 310,922 cwt. in 1885, mainly owing to 

 the attacks of the leaf-fungus Hemileia vastatrix* 



