STEAM GUNS. While Mr. Perkins was making experiments with the high pressure steam of his generator, he observed that all metallic substances were projected from the tube of the stop cock with very great velocity. The idea then occurred to him, that with a gun barrel properly constructed, bullets might be discharged with precision and great force; and upon constructing such a barrel, his expectations were realized. By placing musket balls in a hopper from which they fell in succession into the gun barrel, he was able to project two hundred and forty balls per minute, with a velocity greater than that of gun powder. An ounce ball was discharged from a musket with the ordinary field charge against an iron target, while another similar hall was discharged against the same target from a six feet steam barrel, impelled by steam of forty atmospheres. The distance was the same in both cases; but it was found that the ball dis charged by steam was much more flattened than that discharged by Perkinsunpowder. In another series of expe riments Mr. P projected balls with a force of
one hundred and ten atmospheres; he found that they perforated a block of wood through a greater thickness than those impelled by gunpowder. lie succeeded in throwing a shower of balls at the rate of one thousand per minute. Mr. Perkins avers that he could keep up the same force of steam without intermission for twenty-four hours, or any unlimited time. A very im portant result of these experiments is said to he, that one pound weight of coal is capable of producing a quantity of steam equal in force to five pounds weight of gunpowder. These experiments were the founda tion of Mr. Perkins's patent in 1823, for an improved method of throwing shells and other projectiles be steam. Some farther details respecting the steam-gun will be found in our article SCIENCE, Curiosities in. Vol. XVI. p. 622.
[For an account of Perkins' experiments with his steam-gun, see Franklin Journal, Vol. I. p. 79, and Vol. III. p. 411.]