"Very much, I am aware, has been said in regard to the vitiated air from noxious gases, gunpowder smoke, &c. so often encountered by miners in their subterraneous employ, as giving rise to pulmonary diseases; yet I have long thought that there is another cause which operates still more powerfully, not only in inducing chronic consumption, but also hæmoptysis, and, in the young scrofulous subject, tuberculous phthisis, namely, the mode of ascent from the deeper mines by the ladder—a practice which, under the most favourable circumstances, is, I conceive, highly prejudicial to health. I scarcely need inform you that the miners work two, three, four or five together, for six or eight hours at one time, when they are relieved by another set; though, perhaps, you may not be fully aware of the very imprudent way in which they climb their way up to the surface. I have frequently conversed with miners on this subject, and they have all given me the following account as that which is generally true:— Each miner having taken his portion of the blunted tools on his back, amounting in weight, perhaps to from fifteen to twenty pounds, the most active generally takes the lead, and, at whatever pace, is closely followed, along the horizontal galleries and up the perpendicular ascent of the ladders, by the rest of the party, not only from their desire to keep together, but to avoid a certain slur which would attach to any one falling in the rear. The rapid pace at which they usually set off soon hurries the circulation and respiration, and frequently to such a degree as to give rise to the most distressing feelings. At this time each would slacken his course, although
