Political essay on the kingdom of New Spain (A Borzoi book on Latin America) - Hardcover

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. 1822 Excerpt: ...arrangement is very useful, particularly in mines which employ even 1500 workmen, and in which there is consequently an immense consumption of steel. 1 cannot say much in praise of the method of blasting with powder. The holes for the reception of the cartridges are generally too deep, and the miners are not sufficiently careful in diminishing the mass of the rock intended to yield to the explosion. A great waste of powder is consequently occasioned by these defects. The mine of Valenciana consumed, from 1794 to 1802, powder to the amount of 673,676 piastres t, and the mines of New Spain annually require from 12 to 14,000 quintals. It is probable that two thirds of this quantity is uselessly employed. At Chapoltepec, near Mexico, and in the mine of Ray as near Guanaxua to, some experiments have been made of the method of blasting, proposed by M. Bader; a method by which a certain volume of air must be left between the powder and the wad. Although these experiments have proved the great advantage of the new method, the old has still continued to prevail, on account of the small degree of interest taken by the master miners in reforming the abuses, and perfecting the art of mining. In 1799, 63,375 piastres; in 1800, 68,493 piastres, in 1801, 78,243 piastres; in 1802, 79,903 piastres. The miner is paid at Guanaxuato, for a hole of 1 m. 5 in depth (4 feet 11 inches. Trans.) 12 francs (ten shillings); for a hole of lm. 9 (75.8 inches) in depth, 9 francs (7s. 6d.) without including powder and tools, which are furnished to him. In the mine of Valenciana, nearly 600 holes by two men each are made every 24 hours. t e£l47,377 Sterling. The lining with wood is very carelessly performed, though it ought the more to engage the consideration of the proprietors, as w...