Catoptricae et Dioptricae Sphericae Elementa.
Oxonii [Oxford]: E Theatro Sheldoniano, 1695
Small 8vo, pp. (iv), 99. Engraved vignette on title, woodcut diagrams in the text, including some full-page. Contemporary mottled calf (spine and corners neatly repaired), red edges, marbled endpapers. Title-page a little stained, but a nice copy.
FIRST EDITION. Gregory’s “Catoptricae et Dioptricae Sphericae Elementa (1695) are printed versions of elementary lectures given at Edinburgh in the 1680s…often singled out for its appended remark (p. 98) suggesting, on the analogy of the crystalline and vitreous humours ‘in the Fabrick of the Eye’, that an achromatic compound lens might be formed by combining simple lenses of different media, but this insight he might well have had from Newton” (DSB). DiLaura, Bibliotheca Opticoria, 210: “The notes cover geometrical optics of plane and curved mirrors; images from mirrors; refraction; geometrical optics of refraction at spherical surfaces; images formed by lenses of convex and concave figure; images formed by multiple lenses… The material is concise, detailed, and a mixture of experiment and mathematics including fluxions.”