Highly-concentrated food, having much nourishment in a small bulk, is not favorable to digestion, because it can not be properly acted on by the muscular contractions of the stomach, and is not so minutely divided as to enable the gastric juice to act properly. This is the reason why a certain _bulk_ of food is needful to good digestion; and why those people who live on whale-oil and other highly nourishing food, in cold climates, mix vegetables and even sawdust with it, to make it more acceptable and digestible. So in civilized lands, fruits and vegetables are mixed with more highly concentrated nourishment. For this reason, also, soups, jellies, and arrow-root should have bread or crackers mixed with them. This affords another reason why coarse bread, of unbolted wheat, so often proves beneficial. Where, from inactive habits or other causes, the bowels become constipated and sluggish, this kind of food proves the appropriate remedy. One fact on this subject is worthy of notice. In England, under the administration of William Pitt, for two years or more there was such a scarcity of wheat that, to make it hold out longer, Parliament passed a law that the army should have all their bread made of unbolted flour. The result was, that the health of the soldiers improved so much as to be a subject of surprise to themselves, the officers, and the physicians. These last came out publicly and declared that the soldiers never before were so robust and healthy; and that disease had nearly disappeared from the army. The civic physicians joined and pronounced it the healthiest bread; and for a time schools, families, and public institutions used it almost exclusively. Even the nobility, convinced by these facts, adopted it for their common diet, and the fashion continued a long time after the scarcity ceased, until more luxurious habits resumed their sway. We thus see why children should not have cakes and candies allowed them between meals. Besides being largely carbonaceous, these are highly concentrated nourishments, and should be eaten with more bulky and less nourishing substances. The most indigestible of all kinds of food are fatty and oily substances, if heated. It is on this account that pie-crust and articles boiled and fried in fat or butter are deemed not so healthful as other food. The following, then, may be put down as the causes of a debilitated constitution from the misuse of food: Eating _too much_, eating _too often_, eating _too fast_, eating food and condiments that are _too stimulating_, eating food that is _too warm_ or _too cold_, eating food that is _highly concentrated_, without a proper admixture of less nourishing matter, and eating hot food that is _difficult of digestion_.