Puckerings has dated this piece to the 1900s.
The eye pieces are where the signature can be found "Adjusted In Negretti & Zambra / Opticians London.

They come with a most unusual leather carrying case, velvet and silk lined and gold printed inside the lid again for Negretti & Zambra / 38 Holborn Viaduct, London.
Superb condition measuring 4" x 2 3/8" extending to 3" when fully opened. The case measures 4 1/4" x 2" x 3 1/4" tall. This pair has been painstakingly taken apart with the brass fixtures polished to gleam. A rarely found rather special pair.
Item ID: 32152
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Puckerings has dated this piece to the 1900s.
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