image leybourn_w_on_dialling_1700_pl_018_001
Image number: RS.18014
Credit: ©The Royal Society

Sundial

Date

1690

Creator

Robert White (1645-1703, British), Engraver

Object type

Library reference

48603

Material

Dimensions

height (page): 195mm
width (page): 220mm

Subject

Content object

Description

A plate depicting an instance of ‘projective dialling', where a horizontal dial is projected against a window. A string hangs from the ceiling, adjacent to the meridian line, and a figure lines it up against the light from the sun, thus recording the time.

Inscribed below: ‘Against Page 99 of the Ninth Tractate.’

Plate 18 from William Leybourn’s Dialling: plain, concave, convex, projective, reflective, refractive… (Black Swan, Pater-Noster-Row, 1690)

William Leybourn (1626-1716) British mathematician and land surveyor was not a Fellow of the Royal Society.

Associated place

<The World>
   > Europe
      > United Kingdom