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Show fxMMATION OF SILVER MINES. How Nature Accumulates the Great Store of Valuable Ore. The process by which nature forma her silver mines is very interesting. It must be remembered that the earth' crnst is full.ef water, which percolates everywhere through the rocks, making solutions of elements obtained from them. These chemical solutions take np small particles of the precious metal, which they find here and there. Sometimes Some-times the solutions in question are hot, the water having got so far down as to be set boiling by the internal heat of the globe. Then they rush upward, picking np the bits of metal as they go. Naturally heat assists the performance of this operation. Now and then the streams thus form, ed, perpetually flowing hither and thither thith-er below the ground, pass through cracks or cavities in the rocks, where they deposit their loads cf silver. This is kept tip for a great length of tinie-perhaps tinie-perhaps thousands of years unti the fissure or pocket is filled :iip. Crannies permeating the stony mass in every direction di-rection may become filled with the precious pre-cious metal, or occasionally a chamber be stored ixiii i SS if a lDiKlOU hands were fetching the treasureirom all sides and hiding away a futurmine for some lucky prospector to discorT l mother-age. Pi ttsbarg ijTOtiwit I |