The image above
was adapted from William Cheselden's "Praying Skeleton, in profile", 1733,
etching with engraving, [plate 76 in Cazort, M, M Kornell and KB Roberts
(1996) The Ingenious Maching of Nature: Four Centuries of Art
and Anatomy. Ottawa: National Gallery of Canada, p. 193.
Plate 36 in Osteographia, or The Anatomy of the Bones].