The third cause of the pulmonary consumption above mentioned, is, a spitting of blood, from the bursting of vessels of the lungs, independent of external wound or bruise. People of a fair complexion, delicate skin, slender make, long neck, and narrow chest, are more subject to this than others. Those who have a predisposition to this complaint, by their form, are most apt to be attacked after their full growth: women from fifteen to three-and-thirty; men two or three years later. In Great Britain, a spitting of blood generally occurs to those predisposed to it, in the spring, or beginning of summer, when the weather suddenly changes from cold to excessive hot; and when the heat is supposed to rarify the blood, before the solids are proportionably relaxed from the contracted state they acquire during the cold of winter. When a spitting of blood happens to a person who has actually lost brothers or sisters, or other near relations, by the pulmonary consumption, as that circumstance gives reason to suspect a family taint or predisposition, the case will, on that account, be more dangerous. Violent exercise may occasion the rupture of blood-vessels in the lungs, even in those who have no hereditary disposition to such an accident; it ought therefore to be carefully avoided by all who have. Violent exercise, in the spring, is more dangerous than in other seasons; and, when taken at the top of high mountains, by those who do not usually reside there, it has been considered as more dangerous than in vallies. The sudden diminution of the weight of the atmosphere, co-operating with the exercise, renders the vessels more apt to break. Of all things the most pernicious to people predisposed to a spitting of blood, is, playing upon wind-instruments. Previous to the spitting of blood, some perceive an uneasiness in the chest, an oppression on the breath, and a saltish taste in the spittle; but these symptoms are not constant. Nothing can be more insidious than the approaches of this disease sometimes are. The substance of the lungs, which is so full of blood-vessels, is not supplied so liberally with nerves; the lungs, therefore, may be materially affected, before danger is indicated by acute pain. And it sometimes happens, that people of the make above described are, in the bloom of life, and generally in the spring of the year, seized with a slight cough, which gradually increases, without pain, soreness in the breast, difficulty of respiration, or spitting of blood. A slow fever supervenes every night, which remits every morning, with sweats. These symptoms augment daily; and, in spite of early attention, and what is thought the best advice, the unsuspecting victims gradually sink into their graves.