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Du Pont farmer's handbook; instructions in the use of dynamite for clearing land, planting and cultivating trees, drainage, ditching and subsoiling . d to break floating ice cakes of different thick-ness when the dynamite is exploded on the surface of the ice. Thenumber of charges necessary depends on the size and extent of theice cake: _, . , , , „ , Approximate Number of 1 4 x 1 hickness or Ice Cakes /- • 1 I Carttidees 12 in. 2 to 3 24 in. 6 to 8 36 in. 10 to 12 To open ice gorges already formed, a channel should be cutthrough them beginning on the down-stream side and working upstream alon
Du Pont farmer's handbook; instructions in the use of dynamite for clearing land, planting and cultivating trees, drainage, ditching and subsoiling . d to break floating ice cakes of different thick-ness when the dynamite is exploded on the surface of the ice. Thenumber of charges necessary depends on the size and extent of theice cake: _, . , , , „ , Approximate Number of 1 4 x 1 hickness or Ice Cakes /- • 1 I Carttidees 12 in. 2 to 3 24 in. 6 to 8 36 in. 10 to 12 To open ice gorges already formed, a channel should be cutthrough them beginning on the down-stream side and working upstream along the line of the strongest current. This channel should beabout fifty feet wide, and if the gorge does not move after the channelhas been cut through, it will then be necessary to begin at the down-stream side of the gorge again and widen the channel until the icehas been carried away. To cut the channel, holes are cut with an ax or bar through theice twenty to thirty feet apart. These holes are laid out in a semi-circle with the two end holes about twenty to thirty feet back fromthe open water and fifty feet apart. 63 BLASTING ICE GORGES. DIAGRAM SHOWING LOCATION OF ROW OF HOLES FORBLASTING AN ICE GORGE The charge, consisting of several 11/^ x 8-mch cartridges of RedCross 40% Dynamite, is tied securely together with string, one of thecartridges having been primed with a Victor Waterproof ElectricFuze. When the charges for all of the holes are prepared they are con-nected together and to the leading wires. Each charge is then loweredby the electric fuze wires into the water and pushed under the down-stream ice with the tamping stick. If the current is strong enough tocarry the charge down stream the electric fuze wires should be longenough to let it float six or eight feet below the holes. The explosionof all of these charges simultaneously by the operation of the blastingmachine, will break up the first fifty or sixty feet of the channel and thebroken ice will immediately
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Keywords: ., bookcentury1900, bookdecade1910, bookiddup, booksubjectexplosives