The climate also has its necessities. The inhabitants of the frigid north have an almost insatiable longing for fat. [Footnote: Dr. Hayes, the arctic explorer, says, that the daily ration of the Esquimaux was from twelve to fifteen pounds of meat, one third being fat. On one occasion, he saw a man eat ten pounds of walrus flesh and blubber at a single meal. The low temperature had a remarkable effect on the members of his own party, and some of them were in the habit of drinking the contents of the oil kettle with evident relish. Other travelers narrate the most incredible stories of the voracity of the inhabitants of arctic regions. Saritcheff, a Russian admiral, tells of a man who in his presence ate, at a meal, a mess of twenty-eight pounds of boiled rice and butter, although he had already partaken of his breakfast. Captain Cochrane further adds, in narrating this statement, that he has himself seen three of the savages consume a reindeer at a sitting.] Thus, in 1812, when the Allies entered Paris, the Cossacks drank all the oil from the lamps, and left the streets in darkness. In tropical regions, a low, unstimulating diet of fruits forms the chief dependence. [Footnote: A natural appetite for a particular kind of food is an expression not only of desire, but of fitness. Thus the craving of childhood for sugar indicates a need of the system. It is questionable how far it is proper to force or persuade one to eat that which he disrelishes, or his stomach loathes. Life within is linked with life without. Each organ requires its peculiar nutriment, and there is often a peculiar influence demanded of which we can have no notice except by natural instinct. Yet, as we are creatures of habit and impulse, we need common sense and good judgment to correct the too often wayward promptings of an artificial craving.] WHEN FOOD SHOULD BE TAKEN.--On taking food, the blood sets at once to the alimentary canal, and the energies are fixed upon the proper performance of this work. We should not, therefore, undertake hard study, labor, or exercise directly after a hearty meal. We should give the stomach at least half an hour. He who toils with brain or muscle, and thus centers the blood in any particular organ, before eating should allow time for the circulation to become equalized. There should be an interval of four to five hours between our regular meals, and there should be no lunching between times. With young children, where the vital processes are more rapid, less time may intervene. As a general rule, nothing should be eaten within two or three hours of retiring. (See p 336.)