This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913 Excerpt: ...subaqueous or under water blasting is employed. Drill boats, like the one in the picture, sink the holes in connection with this 'work. In making the necessary holes for the charges, tripod and well drills, obtaining their power from a compressed air main, were used. At one time there were as many as 377 of these ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913 Excerpt: ...subaqueous or under water blasting is employed. Drill boats, like the one in the picture, sink the holes in connection with this 'work. In making the necessary holes for the charges, tripod and well drills, obtaining their power from a compressed air main, were used. At one time there were as many as 377 of these drills at work in the Cut, and they were operated in batteries of from four to 12 drills. The usual depth of the hole drilled was about 27 feet, placed about 14 feet apart, and if all the drill holes necessary for the work were placed end to end, they would equal the length of the earth's diameter from pole to pole with 1,500 miles added. After the holes had been drilled they were widened at the bottom, or "sprung," by a small charge being exploded in them. After sufficient time had elapsed to allow the holes to cool, they were charged and wired. All blasting took place after the men had left the work for lunch or in the evening and at those times a naval engagement could be easily imagined by those living anywhere in the vicinity. At Porto Bello, where much powder was used in the quarrying of rock a series of blasts took place at one time when a British war vessel was passing close to the entrance of the harbor. Hearing what was thought to be the discharge of an Admiral's salute, the cruiser returned the supposed courtesy by dipping its flag. In the Pacific entrance dynamite was employed in subaqueous blasting, two drill barges being used to make the necessary holes. In addition to breaking up hard material for the dredges in this section, the use of dynamite under water kept many of those employed in the vicinity supplied with fresh fish for some time. Those whose employment necessitated their going out in boats considered themselves pa...
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Add this copy of Pictureque Panama and the Great Canal to cart. $70.45, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2010 by Nabu Press.
