burning glass

American  

noun

1. a converging lens used to produce heat or ignite substances by focusing the sun's rays.

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burning glass British  

noun

1. a convex lens for concentrating the sun's rays into a small area to produce heat or fire

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Etymology

Origin of burning glass

First recorded in 1560–70

Example Sentences

See Examples For:

burning glass

He and I know to move around them by sheer memory; the burning glass promises to singe the skin if touched.

From The Guardian ● Apr. 17, 2018

The combination acts as a gigantic burning glass which can melt 130 Ibs. of iron in an hour.

From Time Magazine Archive

Many historians, in fact, have dismissed the story of the burning glass as a myth.

From Time Magazine Archive

Secondly, was his 'into battle' period, when his superb rhetoric and unflinching courage focused like a burning glass the latent will to win of heroic, freedom-loving men the world over, when all seemed lost.

From Time Magazine Archive

A lens, when used for the purpose of collecting the sun's rays, is called a burning glass.

From Conversations on Natural Philosophy, in which the Elements of that Science are Familiarly Explained by Jones, Thomas P.