[SPECTACLE sb.1]
1. A lens of a pair of spectacles.
a. 1583. in Halliwell, Rara Mathem. (1841), 40. For makinge of the smallest sorte of them, commonly called spectacle glasses.
1697. C’tess. D’Aunoy’s Trav. (1706), 146. Proportionably as a Man’s Fortune rises, he increases in the largeness of his Spectacle-Glasses and wears them higher upon his Nose.
1761–9. trans. Voltaire’s Works, XXVI. 196 (Jod.). A lentular spectacle-glass.
1852. Mrs. Stowe, Uncle Tom’s C., I. ix. 128. He … seemed particularly busy in clearing his throat and wiping his spectacle-glasses.
1879. Cassell’s Techn. Educ., II. 177/1. Preference is usually given to bi-convex and bi-concave spectacle glasses.
† 2. A lens used as, or in, a microscope or telescope. Obs.
1671. Grew, Anat. Pl., I. i. (1682), 2. Magnified with a good Spectacle-Glass. Ibid., 20. A lesser sort; which, by the help only of a good Spectacle Glass may be observ’d.
a. 1697. Aubrey, Lives (1898), I. 283. Anno 1678, he [Halley] added a spectacle-glasse to the shadowe-vane of the lesser arch of the sea-quadrant (or back-staffe).
