Why the Wheel Is Round: Muscles, Technology, and How We Make Things Move by Steven Vogel

Author:Steven Vogel [Vogel, Steven]
Language: eng
Format: epub, pdf
ISBN: 9780226381176
Publisher: The University of Chicago Press
Published: 2016-09-14T16:00:00+00:00

Figure 7.5. A so-called seed fiddle or fiddle-bow seeder, used during the latter half of the nineteenth and early in the twentieth century on small farms, plus an old photograph. (See Antique Farm Tools: http://www.antiquefarmtools.info/page3.htm.)

Note that, with a sufficiently loose string, the dexterous operator (bowyer?) can make a shaft of a bow drill or any of its derivatives rotate unidirectionally. All that’s needed is a shaft with enough angular momentum, perhaps one equipped with a flywheel. The bow is moved away from the shaft sufficiently to tighten the loop around the shaft during the power stroke. Then it’s moved closer to the shaft during the recovery stroke so the loop loosens and the shaft continues spinning on its own. While the trick must have been familiar to many ancient drillers, the extent to which the arrangement saw use remains unknown. A friend reports seeing what may have been this device in India, with a short bow, an elliptical motion, and a flywheel to keep the shaft moving.6

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