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 his stomach, he was seized with violent and long continued vomitings. These, though at length they were quieted, left his chest very sore. From this time his cough became troublesome, as did remarkably his shortness of breath upon the least motion, attended with the several circumstances above described.

From considering the history of this disease, and comparing it with the appearance of the lungs after death, I cannot but be of opinion, that the violent efforts to vomit occasioned primarily both the emphysema, and the varices of the pulmonary vein. This opinion, I flatter myself, will not, to persons well versed in the animal œconomy, seem ill founded, when they reflect how forcibly the lungs are pressed in violent efforts to vomit, both by the muscles subservient to respiration and the abdominal muscles, as well as by the contents of the abdomen itself. And it is wonderful, when the texture of the lungs is considered, that accidents of this kind do not much oftener happen, not only in vehement reachings to vomit, but in violent coughs, pains of childbirth, lifting great weights, and other preternatural exertions of strength.

When once the extremities of the bronchia and the vesicular substance have given way, the mischiefs are easily foreseen. The air getting loose into the substance of the lungs cannot be parted with in exspiration; it consequently is retained there, and the space it occupies prevents as much of the external air being received into the lungs as its own quantity. As, from their incessant motion, injuries to the lungs are not easily removed, when once a rupture is made, every fit of couging or other violent exertion extravasates more air. Hence the