[Eyeglasses] B. Martin. An Essay on Visual Glasses, (Vulgarly called Spectacles)

From the Principles of Optics, and the Nature of the Eye, that the common Structure of those Glasses is contrary to the Rules of Art, to the Nature of Things, etc. and very prejudicial to the Eyes (...). The Whole illustrated by a large Copper-plate-print. Second edition, London, printed for the author, and sold at his house, two doors below Crane-Court, Fleet-Street, 1757. 27 pp. with folding copper engraving and 1 page with items invented by Martin, such as a "Megalascope for magnifying large Objects in a beautiful Manner". Small 4to, rebound in 19th-century marbled paper binding.

Rare.