Scientific American Supplement, No. 810, July 11, 1891

Scientific American Supplement, No. 810, July 11, 1891

Scientific American Supplement, No. 810, July 11, 1891The square system of timbering, in use in most of...
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Scientific American Supplement, No. 810, July 11, 1891

Scientific American Supplement, No. 810, July 11, 1891

Dhs. 49.56 Dhs. 24.77

Scientific American Supplement, No. 810, July 11, 1891

Dhs. 49.56 Dhs. 24.77
Author: Various
Format: eBook
Language: English

Scientific American Supplement, No. 810, July 11, 1891

The square system of timbering, in use in most of our large mines on the Pacific coast, was first introduced in Australia by Mr. W.H. Patton, who adopted it in the Broken Hill Proprietary mines, although it does not seem to be so satisfactory to the people there as to our miners, who are more familiar with it. The accompanying description and plans were furnished by Mr. Patton to the report of the Secretary of Mines for Victoria: "The idea is supposed to have originated in the German mines, but in a crude form. It was introduced among the mines of the Pacific coast of America some 20 years ago, by a gentleman named Diedesheimer. Its use there is universal, and experience has evolved it from the embryo state to its present perfection. The old system and its accompanying disadvantages are well known. A drive would be put in for a certain distance, when it had to be abandoned until it could be filled up with waste material and made secure. This process entailed much expense. The stuff had first to be broken on the surface, then sent below, trucked along the drives, and finally shoveled into place. Ventilation was impaired and the drives were filled with dust. The men worked in discomfort, and were not in a condition to perform a full measure of labor. Under the system as adopted in the Proprietary mine, these disadvantages disappear. The cost is one-third less, ventilation is perfect, and every portion of the faces are accessible at all times. Sawn timber is used throughout; the upright and cross pieces are 10 inches by 10 inches, and stand 4 feet 6 inches apart; along the course of the drive, the cross pieces are five feet in length, and the height of the main drives and sill floor sets are 7 feet 2 inches in the clear. In blocking out the stopes, the uprights are 6 feet 2 inches, just one foot shorter than those in the main drives. The caps and struts are of the same dimensions and timber as the sill floor. The planks used as staging are 9 inches by 2 inches; they are moved from place to place as required, and upon them the men stand when working in the stopes and in the faces. A stope resembles a huge chamber fitted with scaffolding from floor to roof. The atmosphere is cool and pure, and there is no dust. Stage is added to stage, according as the stoping requires it, and ladders lead from one floor to the other; the accessibility to all the faces is a great advantage. ......Buy Now (To Read More)

Product details

Ebook Number: 15050
Author: Various
Release Date: Feb 14, 2005
Format: eBook
Language: English

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