 | William Newton, Charles Frederick Partington - 1839 - 478 Seiten
...obtained in the rock at Delhi, which is hard quartz. The line of least resistance not exceeding one foot, a charge of 2 oz. is sufficient ; the line not...4, 5, 6 feet, the charge will be 4, 8, 14, 20, 26, 36 ounces. The author is of opinion, that notwithstanding the increased expenditure of gunpowder when... | |
 | 1839 - 496 Seiten
...obtained in the rock at Delhi, which is hard quartz. The line of least resistance not exceeding one foot, a charge of 2 oz. is sufficient; the line not...tenacity of the rock, but the following may be a general guide:—the line of least resistance being 1, 2, 3, 4,5, 6 feet, the charge will be 4, 8,14,20,26,... | |
 | William Newton - 1839 - 468 Seiten
...obtained in the rock at Delhi, which is hard quartz. The line of least resistance not exceeding one foot, a charge of 2 oz. is sufficient; the line not...tenacity of the rock, but the following may be a general guide:—the line of least resistance being I, 2, 3, 4, 5, 6 feet, the charge will be 4, 8, 14, 20,... | |
 | 1839 - 732 Seiten
...least resistance, and the following results were obtained in the rock at Delhi, which is hard quartz. The charges will vary with the tenacity of the rock,...being 1, 2, 3, 4, 5, 6 feet, the charge will be 4, 8, H, 20, 20, .';6 ounces. The line of least resistance not exceeding one foot, a charge of 2 ozs. is... | |
 | Institution of Civil Engineers (Great Britain) - 1848 - 652 Seiten
...of 2 oz. is sufficient ; the line not exceeding 4 feet, and the rock not being highly chrystalline, 3 oz. per foot will be sufficient. The charges will...guide : — the line of least resistance being 1, 1, 3, 4, 5, 6 feet, the charge will be 4, 8, 14, 20, 26, 36 ounces. On comparing the charges used at... | |
 | Institution of Civil Engineers (Great Britain) - 1848 - 536 Seiten
...obtained in the rock at Delhi, which is hard quartz. The line of least resistance not exceeding one foot, a charge of 2 oz. is sufficient ; the line not exceeding 4 feet, and the rock not being highly chrystalline, 3 oz. per foot will be sufficient. The charges will vary with the tenacity of the rock,... | |
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... the mine abandoned. In large irregular masses of rock, the depth of the bore, or the intervals between the blasts, will generally represent the line of least resistance, and the following results were obtained in the rock at Delhi, which is hard quartz.... 