Page:The American Cyclopædia (1879) Volume VIII.djvu/346

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332 GUNPOWDER to be removed is an important element in the pi-.ihlrm, and that the system which answers Wi-ll in one mine is not necessarily the best in all. For quarries in which stones of certain shape and size are to be obtained, and for such coal mines as employ blasting, of course the shattering effects of charges are specially unde- sirabK' ; and either small charges or slow-burn- ing explosives must be preferred. The amount of ordinary blasting powder required to remove a cubic yard of rock in mining is exceedingly variable, depending upon the nature, structure, and tension of the rock, as well as the quality of the powder and the skill of the workman. This variety is illustrated by the following data, chiefly selected from the records of European experiments, as to the amount of powder re- quired to remove one cubic yard of material : SUBSTANCES. LoaOttM. Powder, Ibi. Rock salt Wieliczka Austria 0'05 Dieuze France ... - 59 Coal Waldenburg, Prussia . . 0-02 Copper schist Silesia, Prussia. ilurtz, " 0-17 0-26 Gypsum 12-43 3'3t Marble Fr nee 8-61 1-62 4 -52 1-92 2'40 3-28 (rothliegendes) . Ha tz, Prussia 4-17 4 -SO Galenite

6-49 8-93 1-31 Clay slate ti 8'51 Quartz H 1-78 (Juartzite Ireland 1-85 Norway . 2-34 Gneiss France 12-30 1-37 4-85 " (firm) France 8'88 Granite Tunnel near New York. 14-97 0'65 An inspection of this table shows how greatly experience varies. It also appears that hard- ness is not the only quality involved in the resistance offered by rocks. Thus gypsum, which is one of the softest rocks, resists blasting by virtue of its lack of firmness and its elasti- city. Native copper can scarcely be blasted at all, on account of its tenacity. (See BLASTING.) The amount of capital and annual product of the gunpowder manufacture in the United States is reported by the ninth census (1870) as follows : STATES. Capital. Value of product. California $573000 $526 427 Connecticut 6861,000 751 000 Delaware 1 400000 77 SOO Massachusetts. . r/ r.'tD 109 000 New York . . . 270 000 547 519 Ohio 150 000 275 000 Pennsylvania 7;,-' 873 033 Tennessee .... 20000 60 000 Wisconsin 20000 82000 Total. . $4020400 $3 991 779 GUN-SHOT WOUNDS GUNS (Hung. K6szeg a town of Hungary, in the county of Vas, on a river of its name, 57 m. S. S. W. of Presburg; pop. in 1870, 6,915. It contains a palace of Prince Esterha/y, a Benedictine monastery, and several churches and educational establishments. Wool is large- ly manufactured, and there is considerable trade in wine and fruits, especially cherries. In 1532 it was besieged by Sultan Solyman the Mag- nificent, with 60,000 men, who made thirteen assaults on the fortifications, all of which were repulsed by a small Hungarian garrison, com- manded by Nicholas Jurisich. GUN-SHOT WOUNDS, injuries caused by the discharge or bursting of firearms. They are of two classes, according as the explosion of the powder does or does not carry solid pro- jectiles. Slight wounds from powder alone are properly burns ; but if the quantity of powder be large or in a confined space, serious contusions and lacerations may ensue. Not only the expansion of the liberated gases, but the unburned portions of powder, and the con- tact of surrounding bodies put in motion by the explosion, are to be considered in these complicated wounds, though their treatment is ordinarily the same as for burns, lacerations, and contusions from other causes. These wounds are purely mechanical, and are more dangerous in proportion to the contiguity to vital organs ; an explosion from a pistol intro- duced into the mouth or near the thoracic or abdominal cavity might prove fatal, while the same on the back or limbs would be trifling. A wound from a musket ball in a fleshy part presents an opening of entrance smaller than the ball in most cases, and with livid and in- verted edges, and the opening of exit, if there be such, larger, more ragged, and with everted edges ; if the ball was fired very near, the en- trance is larger than the exit. These facts often enable an expert to tell the direction and the distance from which a wound was received. The diminished velocity of the ball, its more rapid rotation on its axis, and its consequent more lacerating progress, explain the larger and more irregular opening of its exit. A slight obstacle is sufficient to divert a ball from its original direction, causing singular ec- centricities in its course; a trifling obliquity of surface, or difference of density in the parts struck, may produce the most circuitous pas- sage. A ball may enter on one side of the head, neck, chest, abdomen, or limb, and pass out on the other, having apparently passed di- rectly through, whereas it has really passed entirely round. Spent balls cause injuries of great violence and with little apparent exter- nal wound. These cases were formerly attrib- uted to the wind of the ball, from compression or displacement of air in its course ; but it is now known that a ball after a certain period of its course acquires a rotary motion on its axis, the more rapid as its progress is nearly ended. If a ball with such a motion strike a part of the body, it does not pierce or carry it