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Geology-Mineral District

"Beneath the cliff limestone is a thin stratum of blue limestone, and this rests on a body of brown sandstone. As one goes from the southern townships of Wisconsin towards the north, this blue limestone is observed to become higher and higher in the hills, and the lead diggings to be every where above it. Through the sandstone rocks comes out in bold bluffs on the sides of the hills no veins of ore are ever found in them; but in the cliff limestone above, they are found, though the rock and its fissures lie hid under a great depth of soil.

"These fissures are of every degree of width, from fifty feet down to thin cracks; all of them do not contain ore; the large chambers when they have any [fissures] mineral in them, are lined to the walls with a [thin] coating of lead ore, seldom over a foot thick while the interior is filled with clay. Sometimes across the crevices run horizontal layers of galena; and again it crosses in loose "chunks" in the clay of the fissures or of the soil above, and again it runs in a vertical sheet down, it still again filling narrow fissures in the appearance of a

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