. The Granite monthly : a magazine of literature, history and state progress. ry man decideson which method will best answerhis purpose. Where particular careis not necessary, a large hole isdrilled by hand or steam power, andwhen the hole is drilled to the re-quired depth, it is thoroughly driedof the water used in drilling it, thefuse inserted, and powder pouredinto it, the strength of the chargenecessary to accomplish the purposedesigned being determined by thegood judgment of the sufficient powder has beenplaced in the hole, the remainingportion of it is filled with sand or
. The Granite monthly : a magazine of literature, history and state progress. ry man decideson which method will best answerhis purpose. Where particular careis not necessary, a large hole isdrilled by hand or steam power, andwhen the hole is drilled to the re-quired depth, it is thoroughly driedof the water used in drilling it, thefuse inserted, and powder pouredinto it, the strength of the chargenecessary to accomplish the purposedesigned being determined by thegood judgment of the sufficient powder has beenplaced in the hole, the remainingportion of it is filled with sand orloam, allowing for air space, andtamped down tight with the tampiug-bar, the fuse is lighted, and the quar-rymen retire to a safe place to awaitthe result of the explosion. Dyna-mite cartridges are also used forblasting. Frequently the chargefails to explode, and again the skillof the quarryman is shown in re- - ?5-. lif WW .- m s 4& k :V ,>u - • <?;,*.?? A I — i* a Iff \ Quarryrnen Drilling Holes for Blasting. 2IO QUARRYING AND STONE-CUTTING. r S83. -Aw •, ~ . ... ;- 4 i \-i, 4 4k Boulder Quarrying. moving the old charge so as to inserta new one. This operation is oneof the most dangerous parts of quar-rying, as a spark of fire caused byfriction often explodes the charge,and the quarrymen engaged in thework, having no time to escape, arekilled or maimed for life by suchexplosions. Where there is steampower in a quarry, the holes havebeen blown out by steam, thus avoid-ing danger of explosion. Much depends upon how the blastis made. In the first place the direc-tionsin which a blast will break anykind of rock from the drill hole arebut three, and sometimes four, unlessthe explosive be too quick and forci-ble in its action. The limited num-ber of directions in which the rockis most liable to break is determined by the structure of the rock and theshape of hole. Quick-actingexplosives like dynamite have a ten-dency to shatter the stone. Coarsegunpowder is pr
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