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

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

Suddenly the public gaze converged on them like sunlight through a burning glass, and their names blazed into lights.

From Time Magazine Archive

Because the ancient Greeks did not have the capability of mass-producing glass mirrors, Sakkas decided that the "burning glass" of legend was probably highly polished metal�most likely, the shields of Syracuse's soldiers.

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 powerful telescope glass then furnished a burning glass, and enabled them to get fires once more.

From The Little Gleaner, Vol. X. A Monthly Magazine for the Young by Various