This fatal issue, however, is not invariable. In favourable circumstances, and especially in childhood, the radical constitutional defect may be amended, and with a healthier condition of the blood the unhealthy deposit may cease to take place. The lung-substance, however, with all its curious structure of air-cells and their network of minute vessels where, as in nature's laboratory, the blood receives its due supply of oxygen, is not reproduced. The lung shrinks, the sides of the abscess come together, and by slow degrees a dense material cuts it off from the adjacent healthy structure, but the most complete recovery leaves the patient with his breathing power lessened, and with his vigour consequently more or less impaired. When the deposit is less considerable, a different change takes place. The material dries by degrees, and is at last converted by a purely chemical change into a hard chalky substance, which in the course of time becomes of more than stony hardness. Last of all; when the deposit is smallest in quantity, it may be completely got rid of; and a lung in which consumptive disease once existed, may eventually regain perfect soundness. I have dwelt on these processes as they take place in the lungs; but, allowing for differences of locality, they resemble such as take place elsewhere. Three important conclusions follow from what has been said. First. It is only in quite the early stage of consumptive disease that absolutely perfect recovery can be hoped for. There is a euphemism, more amiable than honest, which doctors not seldom make use of, saying that a child's lungs are not diseased, but only tender. They mean by this, that on listening to the chest, they detect such changes in the sounds of breathing as their experience tells them are usually produced in the early stage of consumptive disease of the lungs. If the opinion is confirmed by a second competent medical man, _then, and not later_, is the time for precautions, for removing the child from school, and for selecting, as far as may be, a suitable winter climate. When the signs of disease are well marked, a reprieve, perhaps a long one, is all that can be confidently reckoned on. Second. When softening of the consumptive deposit has taken place, of which certain sounds attending breathing are all but conclusive, recovery, even the most complete, always implies loss of a certain amount of lung-substance, and consequently loss of a certain amount of breathing power. Third, and this is most important, as well as most cheering; consumption, which is at no age the absolutely hopeless disease that it was once supposed to be, admits of far more cheerful anticipations in children than in grown persons, or, for that matter, than in the youth or maiden.