Reports of the United States Commissioners to the Paris Universal Exposition, 1878. Published Under Direction of the Secretary of State by Authority O

Reports of the United States Commissioners to the Paris Universal Exposition, 1878. Published Under Direction of the Secretary of State by Authority O

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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1880 edition. Excerpt: ... inclined shafts, probably in skin sacks, as is still the practice in some eastern mines. Water must have been got rid of in the same way. The steps in the inclines up which the men went are still visible, as are the niches for earthenware lamps, some of which have been found in place. The use of the perpendicular shafts is not altogether clear. From the dumps surrounding them, M. Cordelia is strongly of the opinion that both the windlass and pulley were known, and that they were used to some extent for.u.1117cutilatins hoisting. The shafts certainly served to promote ventilation, and at the top of some of them is found, ofl'set from the main opening, a sort of chimney, in which a fire was probably built to increase tbe circulation of air. The shafts and inclines are nearly always rectangular aud of about 4 square meters cross-section. The deepest shaft mentioned rij"TM of Lnu" is 393 feet. None of the shafts penetrate to sea-level. The ore as it was removed from the mine in ancient times Ancient con. com rating appa was in part too poor for economical smelting, and was con-TMtus. centrated. Some of the concentrating apparatus, in a fair state of preservation, has been found under heaps of waste. Although, as may be readily imagined, it is not possible to make out from the abandoned apparatus all the details of the process of ore-dressing as practiced by the Greeks, the main features can still be traced. Water was scarce at Laurium and large reservoirs were scarcity of water. built to store a supply. So solidly were they constructed that some of them might even now serve the purpose for vofr"clenl reser' which they were designed. The concentrating apparatus was ingeniously planned to permit the use of the same water over and over...show more

Product details

  • Paperback | 278 pages
  • 189 x 246 x 15mm | 499g
  • Rarebooksclub.com
  • Miami Fl, United States
  • English
  • black & white illustrations
  • 1236520890
  • 9781236520890