English

Noun

burning-glass ‎(plural burning-glasses)

1. (dated) A magnifying lens, as used to focus sunlight on to an object.
   • 1621, Robert Burton, The Anatomy of Melancholy, III.2.2.ii:

     The more he sees her, the worse he is, uritque videndo; as in a burning-glass the sunbeams are re-collected to a centre, the rays of love are projected from her eyes.

   • 1858, R M Ballantyne, The Coral Island:

     Our burning-glass also now became a great treasure, as it enabled me to magnify, and so perceive more clearly […].