=Theobromine= is a white crystalline alkaloid, the exact analogue of caffeine. The latter, in fact, is methyl-theobromine—that is, theobromine _plus_ the theoretical group CH₂. Theobromine possesses similar properties to caffeine. It amounts to 1.5 to 2 per cent. of the whole bean. The ordinary preparations of cocoa differ considerably in composition as may be seen from the following table of per centage composition (Ewell). In each instance other nitrogenous and non-nitrogenous constituents go to make up the total 100: ┌───────────────────────────┬──────┬──────┬──────┬──────┬──────────┐ │ │ FAT. │FIBRE.│CANE- │ ASH. │ ADDED │ │ │ │ │SUGAR.│ │ STARCH. │ │ ├──────┼──────┼──────┼──────┼──────────┤ │_Fry’s Cocoa Extract_ │ 30·9 │ 3·9 │ ── │ 4·2 │ None. │ │_Schweitzer’s Cocoatina_ │ 31·1 │ 3·7 │ ── │ 6·3 │ Do. │ │_Rowntree’s Cocoa Extract_ │ 27·6 │ 4·4 │ ── │ 8·5 │ Do. │ │_Van Houten’s Cocoa_ │ 29·8 │ 4·4 │ ── │ 8·6 │ Do. │ │_Epps’s Prepared Cocoa_ │ 25·9 │ 1·5 │ 26 │ 3·1 │ Much │ │ │ │ │ │ │arrowroot.│ └───────────────────────────┴──────┴──────┴──────┴──────┴──────────┘ Some of the preparations of cocoa (_e.g._ Van Houten’s) have added to them alkaline salts to increase their solubility. Cocoa is not such a valuable food as might appear from the large amount of fat in it, because only moderate quantities of this can be taken without deranging digestion. In Vi-Cocoa a certain amount of kola is added, which contains a considerable proportion of caffeine. The addition of such a drug to a beverage is distinctly to be deprecated. =Minor Stimulants.=—Beverages containing theine, or some analogous principle, appear to be employed in most countries. In moderate doses, they may assist the assimilation of other foods, but their main influence is on the nervous system. Theine-containing substances may be described as both sedative and exciting. They are sedative, in that they allay nervous irritability, and tend to “take the edge off” the disturbance caused by outward circumstances; and they are exciting, inasmuch as they are known to form an admirable antidote to the stupefying effects of opium or alcohol. The wakefulness from tea is an instance of the same thing, while the allaying of sensations of cold and hunger by a cup of tea is an instance of the sedative effect. In Brazil, =Guarana= (from _Paullinia sorbilis_) is used as a drink; it contains theine, the quantity of which is twice as much as in good black tea, and five times as much as in coffee. Like green tea, a cup of guarana infusion is sometimes extremely valuable in nervous headaches.