. Annual report of the Board of Regents of the Smithsonian Institution. Smithsonian Institution; Smithsonian Institution. Archives; Discoveries in science. 394 DRILLING IN STONE WITHOUT METAL. M(:.. the stick and coiled around the stick, as indicated in the drawing. The boAV is then seized with both hands and pressed downwards with a violent jerk> This motion nncoils the string and revolves the shaft towards the left, Init by the action of the fly-wheel the string is coiled again around the shaft in a re- verse manner, and the bow drawn up again. A second jerk at the bow causes the shaft
. Annual report of the Board of Regents of the Smithsonian Institution. Smithsonian Institution; Smithsonian Institution. Archives; Discoveries in science. 394 DRILLING IN STONE WITHOUT METAL. M(:.. the stick and coiled around the stick, as indicated in the drawing. The boAV is then seized with both hands and pressed downwards with a violent jerk> This motion nncoils the string and revolves the shaft towards the left, Init by the action of the fly-wheel the string is coiled again around the shaft in a re- verse manner, and the bow drawn up again. A second jerk at the bow causes the shaft to revolve tow'ards the right, and by continuing this manipulation it is alternately swung around in opposite directions. The operator has it alto- gether in his power to work the appa- ratus slowly or rapidly, and, of course, with coiTesponding effect; but it re- quires some practice to use it in the proper manner. The stone selected by mc for the ex- periment is a flat, oval piece of diorite, of great hardness, not quite seven inches long, about five inches wide, and in the middle part one inch and three-eighths (a little over centimeters)'thick. I chose purposely that kind of stone, be- cause it is the same of which the ancient inhabitants of Europe very often made their pierced implements. It is both hard and tough. These qualities were likewise appreciated by the North American aborigines, who used diorite exten- sively as the material for their tomahawks, large chisels, and pestles. The stone on which I operated is so hard that the point of a well-tempered penknife produces no scratch on its surface, but merely a metallic streak. The material used in drilling was a sharp quartz sand of middle grain, such as is employed in marble-yards; for a short time I also tried emery, but finding that it was not more effectual than sand, I continued to apply the latter. In order to render a beginning of the perforation pos- sible, I tied a small square piece of board in which I h
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