Page:Researches into the Early History of Mankind and the Development of Civilization.djvu/256

246 sure lessening the danger of cracking these brittle materials. One would think that this quality would make the pump-drill particularly unsuitable for fire-making; but nevertheless, by making it very large and heavy, it has been turned to this service in North America, among the Iroquois Indians. Fig. 29 (drawn to a small scale) represents their apparatus, which is thus described by Mr. Lewis H. Morgan:—"This is an Indian invention, and of great antiquity. . . . It consisted of an upright shaft, about four feet in length, and an inch in diameter, with a small wheel set upon the lower part, to give it momentum. In a notch at the top of the shaft was set a string, attached to a bow about three feet in length. The lower point rested upon a block of dry wood, near which are placed small pieces of punk. When ready to use, the string is first coiled around the shaft, by turning it with the hand. The bow is then pulled downwards, thus uncoiling the string, and revolving the shaft towards the left. By the momentum given to the wheel, the string is again coiled up in a reverse manner, and the bow again drawn up. The bow is again pulled downwards, and the revolution of the shaft reversed, uncoiling the string, and recoiling it as before. This alternate revolution of the shaft is continued, until sparks are emitted from the point where it rests upon the piece of dry wood below. Sparks are produced in a few moments by the intensity of the friction, and ignite the punk, which speedily furnishes a fire."

It is now necessary to notice other methods of producing fire which have been found in use in various parts of the world. There is a well-known scientific toy made to show that heat is generated by the compression of air. It consists of a brass tube closed at one end, into which a packed piston is sharply forced