Page:Popular Science Monthly Volume 20.djvu/381

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THE CHEMISTRY OF COFFEE AND TEA.
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the nutrient matters; that, unless in tightly closed vessels, it wastes the fragrance, the qualities held in choicest esteem and highest value; and that, when used with teas, it renders the beverage so strongly astringent as to be both disagreeable and unwholesome.

The opinion is general, though not universal, that coffee is a stronger stimulant than tea, comparing them as American beverages. On this question, the analyst can only aver that a given weight of tea leaf yields about three times as much of the common stimulant principle as the same weight of roasted coffee. How many cups of tea may be made from a pound of the dry leaf, or how few cups of coffee are made from a pound of the browned berry; and how long either quantity, dispensed under regulations both prudent and generous, will continue to supply a flowing cup in daily service of an individual—these questions may be respectfully referred to authorities more competent than chemists. The proper judges can comprise none other than the gracious autocrats of the tea-table themselves; and when they shall have vouchsafed perfectly definite replies, regarding these desired numbers and quantities, then in a very short time some assurance can be given of the stimulating effects of coffee in comparison with tea.

But, pending all conclusion from chemical identity and parallel quantity of constituents, any sufferer from coffee may resort to tea, and any injury from either may be cited against the closest chain of reasoning which chemistry can present. Most people have a small stock of experimental science of their own, sufficient for personal theory, if not wholly in accord with personal practice. And now regarding the effects of coffee in comparison with tea, let it be remembered that sleeplessness during the hours of repose may come from irritation in the stomach as well as from stimulation in the brain. The rich, oily, and albuminoid matters of roasted coffee, and especially the empyreumatic oil to which its flavor is due, are liable to derange the digestion of many persons, while tea is seldom subject to this disadvantage, and its diffusive fragrant oil may be helpful to the action of the digestive powers. In countries where the people rarely have indigestion, it is not found that coffee prevents sleep more than tea, but this report is often made in America, where the digestion is not the best in the world. The astringent influence of tea, unless prepared with brief steeping, may produce ultimate injury, but seldom causes immediate disturbance. To the action of the stimulant alkaloid itself, of course some persons and some nations are more susceptible than others, but we may be sure that it is only from this action that increased mental activity and the wakefulness of nervous exhilaration are obtained, alike in the use of coffee and of tea. And it is doubtless far more from this action of the one alkaloid found in both beverages, than from any other constituents, that their habitual use becomes injurious to many persons.

The consumption of coffee and tea in the United States in one year