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More "Achromatic" Quotes from Famous Books
 ... sweetly the plain-song was dissolved into descant, and how easily they came off with the last rest. Hark, hark, the bitter'st[268] sweetest achromatic. ...
— A Select Collection of Old English Plays, Vol. IX • Various
... with such a combination of lenses, that they may be used double or single, is frequently necessary for the examination of blowpipe experiments, or the reaction of the fluxes. Common lenses, howsoever cheap they may be, are certainly not recommended. A microscope with achromatic lenses can now be purchased so cheap that there is no longer any necessity of procuring one with the common lens. Besides, there is no reliability whatever to be placed in the revelations of the common lens; while on the contrary, ...
— A System of Instruction in the Practical Use of the Blowpipe • Anonymous
... ACHROMATIC. An optical term applied to those telescopes in which aberration of the rays of light, and the colours dependent thereon, are partially ...
— The Sailor's Word-Book • William Henry Smyth
... chromatic aberration, remained insurmountable until John Dollond (born 1706, died 1761), after many experiments, found out how to make an achromatic lens out of two lenses—one of crown glass, the other of flint glass—to destroy the colour, in a way originally suggested by Euler. He soon acquired a great reputation for his telescopes of moderate size; but there was a difficulty in making flint-glass lenses of large size. The first actual ...
— History of Astronomy • George Forbes
... laboratory, the apparatus owned and used by Priestley, which at present constitutes and for many years past has formed an attractive collection in Dickinson College, (Pa.) There would be the burning lens, the reflecting telescope, the refracting telescope (probably one of the first achromatic telescopes made), the air-gun, the orrery, and flasks with heavy ground necks, and heavy curved tubes with ground stoppers—all brought (to Dickinson) through the instrumentality of Thomas Cooper, "the greatest man ...
— Priestley in America - 1794-1804 • Edgar F. Smith
... imagination. Dr. Klein has frequently seen this rill with great distinctness, and at other times sought for it in vain; though on each occasion the conditions of illumination, libration, and definition were practically similar. I have sometimes found this cleft an easy object with a 4 inch achromatic. Again, many rills described by Madler as very delicate and difficult to trace, may now be easily followed in "common telescopes." In short, the more direct telescopic observations accumulate, and the more the study ...
— The Moon - A Full Description and Map of its Principal Physical Features • Thomas Gwyn Elger
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