In a single minute about twenty-five pounds of blood are sent flowing through the lungs, there the whole mass meets the air, sucks in its oxygen, and speeding on carries to every portion of the frame the power which may be said to light up every atom of flesh, nerve, and bone, and to keep the flame throughout the body ever burning with the fresh warmth of life.

In accordance with these facts we find men all over the world acting instinctively. In our climate, either by necessity or choice, we exert ourselves, quicken the blood's speed, breathe rapidly, take in oxygen largely; in short, fan the flame which quick-returning hunger makes us feed. Even the least civilized follow correctly the natural law; the fruit so largely eaten by the native inhabitants of the tropics contains in every 100 oz. not more than 12 of direct heat-producing elements, whilst the blubber and oil of the

Esquimaux has in every 100 oz. somewhere about 80 oz. of such elements. Nor is it possible without injurious effects to live in opposition to this instinct, which science has shown to be in strict accordance with the intention of nature. The Englishman in India provokes a make-believe appetite for meat; he has no notion of changing his home-habits because he has left home a few thousand miles away; he goes to war with sun and air, eats meat abundantly; in short, stops up the grate with throwing on fuel where there is but little of the fiery oxygen to consume it, grows sickly yellow, and so pays in suffering the common penalty of ignorance.

The alderman grows fat, because unfortunately the civic gown adds no oxygen to the atmosphere, and the honour calls him to no especial bodily effort, whilst his dear turtle is scarcely less rich in carbon or warmth-giving food, than the Esquimaux's blubber; and so, as the delightful green fat lacks oxygen to burn it, it stores itself in little cells all over the alderman, a reserve of fuel, like the coals in his cellar. As a contrast we may place the native Indian of the high, dry, clear air of the South American Pampas; at such elevation the air is comparatively scant of oxygen. Of this the Indian knows nothing, but he eats no fat, his sole food is dried lean flesh, and like it he himself is lean, wiry muscled, and wastes little under toil.

So far therefore we have evidence that good may come of method in our cookery. Plum-pudding is no dish for the dog-days, but its suet blunts the keen tooth of winter. Nor is it a mere sentimental sympathy that wakes the wish to give the poor a good Christmas dinner. Scant fare makes cold more bitter. Those who must face the wintry wind unfed, shiver doubly in the blast when they are poorly clad. The internal fire sinks for want of fuel, and the external air drinks up the little warmth the slow consuming system gives.

But this is a digression. We have already spoken of the supposed miraculous doings by which it was taken for granted the stomach could form flesh-making blood out of eatables of all sorts. In infancy we thrive on milk alone. In after years, on bread, meat, and vegetables. Cattle and sheep are a sort of walking machinery to turn grass and grain into beef and mutton, fat and lean, for us. No wonder it should be a puzzle that the very same being could find every part of its body either in milk or mutton, bread or potatoes. Chemistry has, however, solved the riddle, by finding in every form of human food such elements as can be readily changed into the ingredients of the child's first meal, - its mother's milk.

Milk, as every dairy-maid knows, when a little rennet is poured into it, becomes curd and whey. The curd chemists call animal caseine.

When the water in which the meal of peas, beans, or lentils has been for some time suffered to steep, is warmed, and a little acid poured into it, it gives, like the milk, a curd, called vegetable caseine, which is precisely the same as the curd of the milk, and contains, like it, all the ingredients of blood.

So far, therefore, there is no difficulty in understanding how we may live on peas, beans, etc, just as on milk, or meat.

Every one knows that white of egg poured into boiling water, gathers together and becomes firm, the substance so formed is called animal albumen. It is identical with the albumen of the blood.

When vegetables are pounded in a mortar, the fresh squeezed-out juice lets fall a sediment which grass gives largely, and which is also to be had from all kinds of grain. This deposit is precisely the same as the fibrin or lean of flesh. When the remaining clear juice is boiled, a thick jelly-like substance is formed. Cauliflower, broccoli, asparagus, and cabbage are especially rich in this coagulating or thickening substance: it is exactly the same thing as white of egg or animal albumen. It is called, therefore, vegetable albumen, and is, in common with the white of egg, identical with the albumen of blood, which, with the fibrin, whether animal or vegetable, is the source of every portion of the human body.

We see, therefore, that the cattle have, in peas and beans as caseine, in corn and grass as fibrin, in sundry vegetables as albumen, the very materials of their flesh; and that, whether we live upon grain or pulse, beef or mutton, milk or eggs, we are in fact eating flesh, in meat diet ready made; in the case of the others containing the fit ingredients of preparation. Nor are we left in the least shadow of a doubt that albumen of whatever kind is entirely sufficient to produce flesh, for not only do we find every ingredient of flesh contained in it, but we can turn the flesh and fibrin of the blood back to albumen.