. Improving crop yields by the use of dynamite . p,heavy soil than in light or sandy soil. Blockholing This is the most economical method of using dynamite tobreak up boulders, and although it takes some time and labor todrill the one or more necessary holes in the boulder, it will oftenbe found the most satisfactory in the long run. The holes in large 41 HANDBOOK OF EXPLOSIVES boulders should be an inch or more in diameter, while three-quartersor seven-eighths of an inch will answer for the smaller ones. Toproperly break up a boulder weighing about ten tons, a hole shouldbe drilled in it from
. Improving crop yields by the use of dynamite . p,heavy soil than in light or sandy soil. Blockholing This is the most economical method of using dynamite tobreak up boulders, and although it takes some time and labor todrill the one or more necessary holes in the boulder, it will oftenbe found the most satisfactory in the long run. The holes in large 41 HANDBOOK OF EXPLOSIVES boulders should be an inch or more in diameter, while three-quartersor seven-eighths of an inch will answer for the smaller ones. Toproperly break up a boulder weighing about ten tons, a hole shouldbe drilled in it from ten to twenty inches deep, as the shape and grainof the rock may demand, and large enough in diameter to hold apound or more of dynamite with the necessary tamping. Smallerboulders require holes from four to six inches in depth, which, ifnecessary, can be filled full of dynamite, and no tamping used. 30 per cent, dynamite will usually give best results inblockholing, unless the boulders are very large and hard, when 40per cent, should be THE BOULDER—AFTER THE BLAST 42 THE SECOND STAGE Getting the Farm in Shape DIGGING DITCHES DRAINING SWAMPS GRADING ROADS EXCAVATING FOR BUILDINGFOUNDATIONS AND CELLARS SINKING WELLS DIGGING HOLES FOR FENCE-POSTS
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Keywords: ., bookcentury1900, bookdecade1910, bookidimp, booksubjectexplosives
