in reference to spy-glasses or binoculars, 1905, from the firm founded by German optical instrument manufacturer Carl Zeiss (1816-1888).
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The best-known prismatic telescopes are the Zeiss field-glasses.How it Works
But I forgot to yank down those dark filters over the ends of the Zeiss.Cue for Quiet
Thomas L. Sherred
Well, now I will stop, and use my Zeiss glass on the land, which is getting nearer.The Letters of William James, Vol. II
To make sure, I sent my first officer up to the fore-top with an excellent Zeiss glass.
At luncheon-time, when I was about half-way, I sat down with my Zeiss glass—my mother's farewell gift—to look for the valley.Prester John