BLASTING (AS. blast, OHG. bbist, a blow ing; ef. OTIG. blesan, breathe, snort, Ger. blasen, to blow, Engl. blaze, to spread a report, just like the slang blow). The process of breaking up rock, ores, and other fracturable material by means of explosives. It is extensively employed in engineering works generally, and in quarry ing and mining operations particularly. Previ ous to 1613 the means of loosening and breaking up rock in these operations were the hammer, chisel, and wedge, and the process of fire-setting, which consisted in heating the rock surface by building wood-fires against it and then quickly cooling it with water, the sudden contraction thus produced causing the material to spall off and crack open to a limited depth. The first attempt to blast rock by the use of an explosive is commonly credited to Martin Weigel, a mine boss at Freiberg. Saxony, and is said to have oc curred in the year 1613. Whether this date is ac curate or not, it is quite certain that any previ ous attempts at blasting were so exceptional that they did not come to the notice of the several writers on mining of that early date. Whatever
niay have been the date of the first attempt at blasting. however, it is certain that by 16:34 to 1644 the use of gunpowder in mining operations was quite generally known in Germany. From that country the process was taken by German miners to England in 1670, and to Sweden in 1724. Until 16S5 the drill-holes were stopped with wooden plugs, but in that year clay-tamping was employed in Saxony. In 1791 sand-tamping was first used. Hand-drilling with cone and crown drills was used until 1759, when the mod ern chisel-edge drill was introduced. In 1829 Moses Shaw. of New York, first fired blasts by electricity, and in 1531 Bickford, an Englishman, invented the match or fuze now known by his name. (See FuzE.) In 1849 Mr. J. J. Couch, of Philadelphia, Pa.. invented the first power per cussion drills. (See Daiii.s.) In 1863 nitro glycerin, and in 1867 dynamite, were first used as explosives in blasting operations. See Ex