Scarce first edition of this landmark printed work in the very early development of achromatism.
Indeed, in this book, Gregory gave the first hint of the achromatic doublet (writting about the catadioptric Newton telescope) when he referred to the possibility of counteracting colour aberration in lenses by combining in them media of different densities.
It’s the first idea of the so famous futur achromatic doublet lens finally invented during the 18th century for telescopes’s objectives and during the years 1820s’ for the microscopes’s objectives.
So, a seminal step in the developpment of application of optics to optical instruments for macro or microscopic observations.
Gregory’s Treatise of Practical Geometry and Catoptricae et dioptricae sphaericae elementa (1695) are printed versions of elementary lectures given at Edinburgh in the 1680’s; the latter is 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 : “‘Perhaps it would be of service to make the object lens of a different medium, as we see done in the fabric of the eye; where the crystalline humour (whose power of refracting the rays of light differs very little from that of glass) is by Nature, who never does anything in vain, joined with the aqueous and vitreous humours (not differing from water as to their power of refraction), in order that the image may be painted as distinct as possible on the bottom of the eye”
GREGORY (David), Catoptricae et dioptricae sphaericae elementa, Oxford, Sheldonian Theatre, 1695
8vo, IV, 99 and (1) pages ; English contemporary calf (joints very fragile).
Inside very clean and untouched.
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Established by Alexandre Piffault in 2014 and based in Paris, Le Zograscope specializes in antique and rare books in Science, Medicine and Technology, and rare antique instruments in the same fields. We have especially a strong interest in early and continental microscopy, early and special mathematical/drawing instruments, medical and surgical instrument, and rare technology.