A supplement to Ures Dictionary of Arts, Manufactures, and Mines, : containing a clear exposition of their principles and practice. . to a proper size for the bucking-hammer or crushing-mill, and at the same time to cast asidesuch lumps as are destitute of ore. The hammer employed is made of cast steel, and is setupon a light pliant handle. Its weigkt is about sixteen ounces, and its cost eightpence. Apractised spaller will produce about one ton of stuff per day, but the quantity must neces-sarily depend upon the hardness and nature of the stone. Cobbing, Jig. 473.—This work is also generally
A supplement to Ures Dictionary of Arts, Manufactures, and Mines, : containing a clear exposition of their principles and practice. . to a proper size for the bucking-hammer or crushing-mill, and at the same time to cast asidesuch lumps as are destitute of ore. The hammer employed is made of cast steel, and is setupon a light pliant handle. Its weigkt is about sixteen ounces, and its cost eightpence. Apractised spaller will produce about one ton of stuff per day, but the quantity must neces-sarily depend upon the hardness and nature of the stone. Cobbing, Jig. 473.—This work is also generally performed bywomen or young girls. It consists of picking the best work fromthe dradge, and with a peculiarly shaped hammer detaching fromeach piece the inferior portions, and thus forming either prill orl>est dradge ore. An expert cobber will manage to pass throughher hands about ten hundred weights of tolerably hard stuff perten hours. Apparatus.—In the varied processes of dressing, nopoint is of greater importance than that of correctly sizing thev^in stuff, neither is there one demanding the exercise of a mor
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Keywords: ., bookcentury1800, bookdecade1860, bookpublishernewyo, bookyear1864
