While the lungs and heart are doing better work under the stimulus of muscular exercise, the heart pumping the blood more certainly to the farthermost tissue of the body and the lungs more rapidly purifying the blood, other organs are benefited. The diaphragm, that muscle separating the lungs and heart from the stomach and liver, is rising and falling, and, with the increased expansion and contraction of the walls of the thorax, is moving all the contents of the abdomen to activity. The liver, the great gland of the body, has not only more blood sent to it, but is quickened to action. For bilious people there is no medicine like exercise and fresh air. In malarial districts, bilious people are most easily affected by the malarial poison. Though in such districts a great many troubles are conveniently laid at the door of that enemy of health which do not justly belong there, yet of the fact that some are affected by it, and others equally exposed are not affected by it, may not the explanation be, that an active circulation in one person effects the elimination of the poison through the excretory organs so rapidly that it can not collect in sufficient quantities to cause disturbance of the system? In the case of a person affected by a stupefying poison, the first thing to be done is to keep the individual moving; that is, to keep the circulation going by exercise till the poison can be eliminated. The laboring-man who works at a sewer in front of a house seldom feels any ill effects from the overturned soil and poisonous gas, while some dweller in the house, apparently not so much exposed, is stricken with typhoid or malarial fever. Causes of the immunity of the workman may be found in his greater strength and feebler sensibility, and in his open air life; but may not another reason be seen in the quickened action of his lungs and the profuse perspiration of his skin? As to the effect of want of exercise on the liver, the following passage may be quoted from an authority on the subject: "A want of exercise in the open air leads to derangement of the liver in two ways: viz. (a) By causing a deficient supply of oxygen to the system, as a result of which the oxidizing processes, which go on in the liver and elsewhere, are imperfectly performed, and there is a tendency to the accumulation in the system of fat and the imperfectly oxidized products of disintegrated albumen. Oxygen is, so to speak, the antidote for the destruction of materies morbi (lithic acid, etc.) produced by imperfectly oxidized albumen, (b) By retarding the circulation of the blood through the liver. Since the time of Haller (1764), physiologists have recognized the influence of the respiratory movements in producing the circulation of blood through the liver; but upward of thirty years ago Mr. Alexander Shaw showed more clearly than ever before that the circulation of blood through the liver was greatly influenced by the alternate expansion and contraction of the thorax during respiration. Mr. Shaw called attention to the fact that the portal vein, without any provision for increasing its power, 'has to perform
