. Transactions. i Mine Timbering in the Old Ironsides and Knob Hill Mines. 441 \ ^^^^2>2.^. ?^^^^^?^^^ 442 The Cufiatiiati Mining Institute. Timber is moved about the upper floors by means of a pair of steeltongs like ice tongs. As yet no reinforcing sets have been used. Heavy ground is heldby putting in diagonal braces, or by extra spragging and cribbing withsolid timber cribs built in between the rock and the regular sets toprevent a fall beginning. In the centre of the large stopes cribs filled with waste rock or, insome cases, with ore are carried from the bottom level up with th
. Transactions. i Mine Timbering in the Old Ironsides and Knob Hill Mines. 441 \ ^^^^2>2.^. ?^^^^^?^^^ 442 The Cufiatiiati Mining Institute. Timber is moved about the upper floors by means of a pair of steeltongs like ice tongs. As yet no reinforcing sets have been used. Heavy ground is heldby putting in diagonal braces, or by extra spragging and cribbing withsolid timber cribs built in between the rock and the regular sets toprevent a fall beginning. In the centre of the large stopes cribs filled with waste rock or, insome cases, with ore are carried from the bottom level up with thetimber; this is intended to steady the timbering in the stop2. Thisfilling pillar is usually 15 or 20 feet square and is retained by largelagging split and placed behind the posts. Where a turntable is put in the track in the bottoms of stopes apost is left out at opposite corners to allow of long timbers being turned;an 8 X 8 inch upright is bedded on rock beside the adjacent posts anda 12 inch square timber on top of these supports the regular caps. On the bottom of the stopes shutes for drawi
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Keywords: ., book, bookcentury1800, booksubjectmineralindustries, bookyear1895
