may show these characteristics, but also those of parents generally enfeebled, or whose ages are widely separated, or who are closely related by blood, or of a mother who has previously borne a number in quick succession. Even when heredity is sound, the same condition is sometimes induced by coddling, by improper feeding, by attacks of acute disease, or by want and distress. In growing children, a bad carriage of body may act injuriously by contracting and deforming the chest. The stooped position which boys sometimes assume in bicycle-riding should be discouraged for this reason.
Before the period of bacteriological research conditions thought to bear a causative relation to consumption were eagerly studied. Some of these thought to be important, it can now be seen, were principally operative by affording favorable circumstances for contagion, or were themselves symptoms of disease already present. They still teach useful lessons, however, and deserve more attention than is at present given them. We all know now the reason why bad air was for so long regarded as a cause of the disease, but it still remains the fact, nevertheless. Imperfect food supply was also assigned a place among the causes, but second to an imperfect supply of pure air. Well-fed factory operatives who work in close rooms are much more prone to the disease than poorly fed laborers who work outdoors. A French laborer moved to Paris with his wife and three sons from the country, where they had worked outdoors. The father and two of the sons soon died of tuberculosis; the mother and remaining son returned to the country and survived. This illustrates the well-known fact that the mortality increases with the density of population, being greatest in large cities and in barracks, prisons, and factories. Sixty-seven per cent of the deaths among the Guards in the English army are due to it. The death-rate in prisons increases steadily with the years of confinement, and diminishes as ventilation is improved. Inadequate nutrition because of insufficient food supply or of indigestion, which in turn may be the result of improper or poorly prepared food, undoubtedly predisposes to the disease. The same may be said of exhausting discharges or hæmorrhages, of childbearing, of enervating habits or practices, and of depressing emotions, all of which tend to reduce the resistive power of the body. Considerable importance has been attached to damp soil, and it would seem justly so. Dr. Buchanan, of England, found that the drainage of such soil always reduced the death-rate among the inhabitants of the region. Dr. Bowditch, of Boston, says that three fourths of 201 cases investigated by him lived in houses built on damp soil. He observed also that the death-rate was lowered by draining. He mentions several specific instances, among them the following: A and B married sisters.