The Chemistry of Cookery

commonly attributed to Liebig, but which is Lehmann’s, published in Liebig’s ‘Annalen,’ vol. lxxxvii., and adopted and advocated by Liebig with his usual ability. Lehmann watched _for some weeks_ the effects of coffee upon two persons in good health. He found that it retarded the waste of the tissues of the body, that the proportion of phosphoric acid and of urea excreted by the kidneys was diminished by the action of the coffee, the diet being in all other respects the same. Pure caffeine (which is the same as theine) produced a similar effect; the aromatic oil of the coffee, given separately, was found to exert a stimulating effect on the nervous system. Johnston (‘Chemistry of Common Life’) closely following Liebig, and referring to the researches of Lehmann, says: ‘_The waste of the body is lessened by the introduction of theine into the stomach—that is, by the use of tea._ And if the waste be lessened, the necessity for food to repair it will be lessened in an equal proportion. In other words, by the consumption of a certain quantity of tea, the health and strength of the body will be maintained in an equal degree upon a smaller quantity of ordinary food. _Tea, therefore, saves food_—stands to a certain extent in the place of food—while, at the same time, it soothes the body and enlivens the mind.’ He proceeds to say that ‘in the old and infirm it serves also another purpose. In the life of most persons a period arrives when the stomach no longer digests enough of the ordinary elements of food to make up for the natural daily waste of the bodily substance. The size and weight of the body, therefore, begin to diminish more or less perceptibly. At this period _tea comes in as a medicine to arrest the waste_, to keep the body from falling away so fast, and thus to enable the less energetic powers of digestion still to supply as much as is needed to repair the wear and tear of the solid tissues.’ No wonder, therefore, says he, ‘_that the aged