A paper, on the patent azimuth and steering compass invented by E.J. Dent ... [together with a paper on the shape of the wheel-teeth in the clock for the new Royal Exchange] / Presented to the ... British Association for the advancement of science ... 1844.

  • Dent, Edward John, 1790-1853
Date:
1844
Catalogue details

Licence: Public Domain Mark

Credit: A paper, on the patent azimuth and steering compass invented by E.J. Dent ... [together with a paper on the shape of the wheel-teeth in the clock for the new Royal Exchange] / Presented to the ... British Association for the advancement of science ... 1844. Source: Wellcome Collection.

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    A PAPER ON THE SHAPE OF THE WHEEL-TEETH IN % Cf)e (illocfe for tije Keio i^o^oal iSrcljange. PRESENTED TO THE MEETING OF THE BRITISH ASSOCIATION AT YORK Bead SOlh September, 1844. BY EDWARD J. DENT. It will perhaps bo generally admitted, that the geome¬ trical form of the wheel-teeth in Chronometers, Watches, and Clocks, is but seldom or ever attended to by the persons who either cut the wheels or make the pinions ; and it may be explained from the circumstance of these operations being separated into two distinct trades. The system pursued by workmen to insure what they suppose to be the proper form of the wheel-teeth, is, that it should, as nearly as possible, resemble “ the shape of a hay-leaf?'' The terms geometrical circles or pitch lines are not understood. Having taken some care with the curves used in the Clock in question, and believing it may prove advantageous, if the same system be generally adopted in the con¬ struction of the teeth of wheels in such machines, I am induced to lay this communication before the British Association. As the wheels in a Clock move in one direction, an