Albert Benjamin Prescott,
Popular Science Monthly
(1882)
“ In chemical analysis coffee yields an alkaloid, at first named caffeine, but long since determined to be identical with the alkaloid of the tea-plant, so that while the terms theine and caffeine are both in use, chemists recognize them as synonyms. Theine is found not only in the seed—the "berry" of the coffee-plant but even more abundantly in the leaf, though the latter, of less agreeable flavor, has been little used, and is not in commerce. The use of the coffee-leaf is further discouraged by the fact that the plucking of the leaf is injurious to the crop of the berry. ”
