Page:Transactions of the Provincial Medical and Surgical Association, volume 2.djvu/121

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gradually accumulates, so as to form puddles and pools, of considerable size, under the feet of the miners; and it is very common to find the bottom of long galleries covered, for some hundred feet, with dirty water of this kind, to the depth of several inches, and sometimes of a foot or more; sometimes, but very rarely, we meet with brisk stream lets or springs gushing from the lode. In most mines we meet with currents of water flowing towards the pumps from the upper galleries, or from parts of the mine that have been abandoned.

The quantity of water in mines is most abundant during the winter, of rather in the spring, some time after the termination of the rainy season. This fact is easily accounted for, especially in deep mines, by the length of time that the superficial water requires to percolate to a considerable depth. Inattention to this circumstance has given rise to an idea, still prevalent among miners, that a dry easterly wind raises the springs. The fact seems to be, as has been satisfactorily shown by Pryce, that the "dry easterly winds," of the spring generally set in, in this country, about the period at which the main body of the rain, fallen in the preceding months, has been able to attain, in its slow progress through the lodes and strata, the bottom of the mines. The variation, in the quantity of water is much more considerable in shallow mines; these soon experiencing the variations of humidity at the surface, according to the seasons. It is a curious fact that several mines worked under the sea, have been found less subject to the percolation of water from above than many others. This was formerly observable