is completed in twenty minutes. Besides ensuring greater cleanliness, the making of bread by machinery saves time, and tends to improve the sanitary and moral conditions of the bakers, a subject which has attracted much attention lately. Brown bread has been long considered "wholesome," the bran containing gluten and a ferment which converts starch into sugar, the bread being thus more rapidly digestible. The insoluble matters stimulate the bowels and prevent constipation. Stale differs from fresh bread more in the arrangement of its molecules than in the amount of water, for bread loses but of its water in five days; it will get stale in moist air, and become fresh again by being placed in the oven, where water must be driven off. The principles of Dietetics may point out approximately the proper quantity of food, but no exact standard can be fixed, individuals varying so much under the influence of habit, climate, labour, &c. The following is the diet scale of the British "There shall navy: be allowed to every person the following quantities of provisions: bread 1 fb, beer 1 gallon, cocoa 1 oz., sugar 1 oz., fresh meat 11b, vegetables tb, tea oz. When fresh meat and vegetables are not issued, there shall be allowed, in lieu thereof, salt beef lb, and flour alb, alternately with salt pork 1b, and pease pint, and weekly, whether fresh or salt meat be issued, oatmeal pint, vinegar pint." The following dietaries are given (on the authority of Playfair) in ounces per week: ... 127-18 71.68 4.92 127.76 85.25 4.62 English soldier... 378 36.15 The following are the articles of the diet-table of the military hospitals: As dietetic extremes, may be mentioned the Esquimaux, one of whom, Captain Parry states, consumed 35 lb of solid food in 24 hours; and Cornaro, who subsisted for 58 years on 12 oz. of food, and 14 oz. of light wine daily. Nature's promptings, if attended to, afford the surest guide, the more so if repletion be prevented by allowing due periods for the acts of mastication and other preparatory processes-when the system has time to intimate, by the feeling of satiety, that its wants have been supplied. The time of meals must vary much with habit and ranks of life, but at least sufficient interval should elapse between each meal to allow stomachic digestion, and the processes which follow it, due time. In children, waste and repair of tissue is more rapid, and the intervals between meals should be shorter. It has been calculated, that while an adult consumes daily 43 grs. of carbon and 13 grs. of nitrogen for every tb of his weight, an infant requires 136 of carbon and 10% of nitrogen. In them, also, the appearance of each class of teeth suggests a change of food—thus, flesh may be given when their canine teeth are developed. Before describing the processes to which food is subjected, we will briefly discuss the symptoms which indicate that it is required—namely, hunger and thirst. Hunger is a feeling, varying in degree from the agreeable promptings we call "appetite," to the horrors of "starvation." It becomes an important social question, when it is remembered that it may be regarded as a great stimulus to human labour, or a powerful incentive to crime. Its dependence on the waste of tissue is shown by its greater force and more rapid recurrence in young animals, and those who consume much oxygen, than in the cold-blooded and hybernating classes. The proximate cause of hunger would seem to be some influence on the branches of the pneumogastric nerves, for Brachet, after letting a dog become ravenously hungry, divided these nerves, and the animal lost all desire for food. This experiment, however, in the hands of Reid, yielded somewhat different results. Narcotics, also, destroy appetite, by acting on the nervous system. Beaumont believed that it was produced by gastric juice being retained in the follicles, and pressing against the nervefilaments. However, that fluid is not secreted during fasting, and the first portion of food would empty the follicles, yet does not appease hunger. Others regard it due to the scanty supply of blood the organ receives during fasting. The feeling is sometimes subjective or dependent on conditions of the nervous system itself; and, again, the effect of the depressing passions on it is well known. Although mainly a systemic indication, mechanical distention of the stomach will relieve hunger, as by the introduction of clay, which many races are said to resort to. Want of food is then indicated by a sinking sensation about the gastric region, general faintness, and the secretion of gas. If such promptings are not attended to, the prostration increases, the lymphatics absorb greedily, the individual feeding on himself, the voice becomes feeble, the eye sunken, yet terribly brilliant and wild, and the agonies of starvation are established; animal heat falls rapidly, delirium occurs, and death takes place about the fifth or sixth day, or as soon as the loss of weight amounts to two-fifths. Life will be sustained much longer under the influence of syncope, hysteria, hallucination, and other nervous diseases.— Instances of prolonged fasting are much exaggerated, and are generally cases of imposture, having deceived, however, such careful observers as Berard, Burdach, &c. Sloane relates that a man was rescued alive from a coalmine after being confined 23 days, during which he took nothing but some foul water for the first 10 days. It is stated that the stomach is unable to digest, and that loathing for food occurs some days before death. The well-known experiments of Chossat on starvation prove that the tissues waste in the following order, and most rapidly as death approaches: the adipose, muscular, osseous, and nervous. The slowness with which the nervous matter wastes is remarkable, remembering the large amount of fat it contains, and may depend on the difficulty of absorption through the neurilemma of the tubes. After death, the stomach and intestines are found shrunken, rugous, and extremely thin, the gallbladder over distended, the bile not being used or neutralized; the other secretions and blood are found scanty. The rule that death occurs when the loss amounts to two-fifths, holds good for nearly all animals, yet the time of death varies remarkably, birds succumbing within a week, and if Rudolphi can be credited, the proteus living five years without food. Another exceptional case was reported to the Linnean Society, where a pig lived 160 days, buried under a chalk bank, having lost 75 per cent. of its weight, chiefly fat. As the introduction of new matter by food helps to expel the effete matter of the tissues, starvation kills partly by the retention and decomposition of this matter producing a form of putrid fever, and putrefaction rapidly occurs after death. The connexion between want of food and zymotic diseases is admirably shown in Dr. Corrigan's essay on "Famine and Fever as Cause and Effect in Ireland." The curative effects of food in the disease was forcibly taught by Dr. Graves, who wished that his epitaph might be, "He fed fevers." Thirst, although marked chiefly in the mouth and pharynx, is a systemic sensation, as the injection of water into the veins or the stomach will relieve it. Bernard has shown this by producing a gastric fistula in a dog; the animal drank incessantly while the fistula was open, as the water was not absorbed, but was satisfied with a small quantity when it was closed. In the words of Mayo," a person might be hungry without a stomach, and thirsty without a throat." Even a moist air, or bathing, will slake thirst-hence the renowned Franklin advised sailors, when the supply of water fell short, to bathe and to damp their clothes. This practice is not safe if food also be insufficient, as it tends to lower animal heat, and should now be unnecessary, since Dr. Normandy's process of separating pure water from sea-water by destillation has been adopted. The sersation of thirst would seem sometimes to be absent, as Sauvages relates of a member of the Toulouse University. The feeling may be subjective, and spices and stimulants applied to throat will produce it, although there is no want of water in the system. The symptoms of thirst are a dryness and clamminess of the mouth and pharynx, the tongue feels as if sticking to the palate, respiration is obstructed, and nervous irritability is heightened to an extreme degree. The blood cells have been found shrivelled by exosmose of their water. Death occurs sooner than from deprivation of food, and with even greater distress, as seen in some of the persons confined in the black-hole of Calcutta. Ice and, what is remarkable, tepid water are superior to equal quantities of cold water for slaking thirst, as we see in fevers and diabetes. Thirst kills by exciting pyrexia. The Stages of Digestion were, according to Magendie-1. Prehension; 2. Mastication; 3. Insalivation; |