Image: Verge escapement Giovanni di Dondi
Description: Drawing of the verge escapement in Giovanni de Dondi's astronomical clock the 'Astrarium', built 1348-1364, Padua, Italy. From Tractatus Astrarii, a manuscript by Giovanni de Dondi around 1364. The caption claims this is the earliest existing drawing of a verge escapement. The crown shaped wheel at top is the clock's balance wheel, which had an oscillation period of 4 seconds. The escapement is just below it. The crown wheel is drawn with 24 teeth, which must have been an error, because verge escapements require an odd number of teeth to operate. Alterations to image: cropped out caption, converted to JPEG.
Title: Verge escapement Giovanni di Dondi
Credit: Retrieved May 31, 2008 from John David North (2005) God's Clockmaker: Richard of Wallingford and the Invention of Time, Hambleton & London Co., London, UK, ISBN:1852854510, p.179, fig.33 on Google Books. Credited in the caption to Giovanni de Dondi's 1364 manuscript Tractatus Astrarii in MS 631, Biblioteca Civica, Padua, folio 13r.
Author: Giovanni de Dondi
Permission: Public domain - author died in 1389
Usage Terms: Public domain
License: Public domain
Attribution Required?: No
Image usage
The following page links to this image:
