Inventory no. 53463 - contemporary illustrations
A curve bow with three screws is shown in Thomas Tuttell's engraved plate for the revised edition of Joseph Moxon's Mathematics made Easie (1701). Reproduced on p. 37 of Maya Hambly's Drawing Instruments 1580-1980 (1988).
Tuttell's set of mathematical playing cards (1700) has the Bow as the 7 of Hearts, with the description "An Instrument to draw large Arches, where their Centors are at a great distance used in Projecting of the Sphere". There are sets of these at the British Museum and elsewhere. See
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