We have here to consider the sources of the three leading dietetic beverages. They are very unlike in general appearance, but all possess the same vegetable principle, called an alkaloid,[1] though known under different names. Thus modern chemistry has proved the identity of the theine of the tea, the caffeine[2] of the coffee and the theo-bromine[3] of the chocolate. This same vegetable alkaloid, remarkable for its large per cent. of nitrogen, is found in small quantities in a few other plants, most of which have been used to some extent for the making of an exhilarating drink. It answers our purpose best to treat each of our three subjects under its respective head. TEA (_Thea viridis_[4]).—The tea of commerce is the prepared leaves of a shrub belonging to the order Camelliaceæ[5] represented in the United States by loblolly bay[6] and Stuartia.[7] Perhaps the most familiar near relative of the tea plant is the camellia of our green houses and window gardens. The wild tea shrub grows from twenty to thirty feet high, and is found native in China and Japan. When under cultivation the shrub is pruned so as to not exceed six feet in height. The flowers are large, white and fragrant; they are produced in clusters in the axils of the simple, oblong, evergreen, serrate leaves. China and Japan are among the leading tea-growing countries, its cultivation being chiefly confined between twenty-five and thirty-five north latitude. Tea was in general use in China in the ninth century, but it was not until the seventeenth century that it was introduced into Europe. About the middle of this century the East India Company imported tea into England, since which time it has become the regular beverage of many millions of people in all parts of the world. The importations of tea into the United States for the year ending June 30th, 1884, were 67,665,910 pounds. It will be seen that this gives somewhere near a pound and a quarter of tea for each man, woman and child in this country. Most of our China tea trade is carried on with Shanghai, Foo Chow and Amoy.