burning-glass
(ˈbɜːnɪŋ glɑːs, -æ-)
A lens, by which the rays of the sun may be concentrated on an object, so as to burn it if combustible.
| 1570 Dee Math. Pref. 35 Archimedes..with his Burning Glasses..fired their other Shippes a far off. 1598 Shakes. Merry W. i. iii. 74 The appetite of her eye did seeme to scorch me vp like a burning-glasse. 1643 Caryl Sacr. Covt. 33 The fiery beames of Gods wrath are contracted into this burning-Glasse. 1727 Swift Gulliver iii. i. 180, I had about me my flint, steel, match, and burning-glass. 1768 Tucker Lt. Nat. II. 426 Not unlike the virtuoso's scheme, who would needs try to make a burning-glass of ice. 1878 Masque Poets 213 Beauty is a burning-glass that brings The soft, diffusive sunshine to a focus. |
b. A concave mirror, by the use of which the same effect may be produced.
| 1675 Baxter Cath. Theol. i. iii. 11 The Spirits effect on the soul to come by reflection..as Light and Heat from the Sun by a Speculum or Burning-Glass. 1751 Chambers Cycl. s.v., The second..are concave; very improperly called burning-glasses, being usually made of metal. 1760 tr. Keysler's Travels I. 428 A concave burning-glass reflects..the solar rays into one focus. |