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 film begins with a helicoptic view, swooping over the dome of St. Peter's, then briefly darts away to Greece to catch the sun's rays igniting the traditional torch through a burning glass at Olympia.

From Time Magazine Archive

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

From Time Magazine Archive

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

From Time Magazine Archive

It was exciting enough for those who looked on, but their feeling was gathered in his, like light in a burning glass.

From The Childhood of Rome by Lamprey, Louise