xed with sand, or between layers to the side bers, makes less joints for wear and prevents the coarse sand, 15 parts spongy iron mixed with one-third its of sand and gravel, so long used for filtering purposes, has a swing of the body forward and backward that would other- bulk of fine gravel, laid… … white miners average $2.25 cents per day, the and one-half. the depth of the top layer, ‘and re- men boarding themselves. Blacksmiths and placing with fresh sand., other mechanics and overseers are paid $4 per The double filter cistern, Fig. 2, has much to day. The Great Eastern mine employs 35…
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