none dare propose to do so; and thus they go on till they reach "grass," when they find themselves completely overpowered by the excessive action of the heart and lungs, so as to be wholly unable for some time to speak. Is it surprising, then, that the miner, of all men, should be the most subject to hæmoptysis, and to pleuritic and pulmonic stitches, so constantly. in them, demanding the use of the lancet and blisters?
"That the heart, and the great blood-vessels thereunto appended, are often the seat of disease in the miner, the numerous examples of their irregular and disordered functions, so often terminating in hydro-thorax, and the frequent rupture of blood-vessels, too probably indicate. It would, indeed, seem to me altogether impossible that the whole circulating and respiratory systems within the chest, could long suffer such inordinate and preternatural actions with impunity. I conceive, also, that when the lungs have been thus over-excited, the full and quickly repeated inspirations of cold air, during the winter season, which the men are obliged to take immediately on reaching the surface, and to continue for some time, must act inimically on the delicate network of blood-vessels of the bronchial tubes. Such sudden changes must give rise to, and keep up, a degree of subacute inflammation, and consequent thickening of the mucous membrane of the bronchia, frequently obstructing their cavities, and that of the air cells, producing dyspnœa and expectoration, and ultimately terminating in the disease which I have termed chronic consumption.
"The mining district of Cornwall would, I conceive,
