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Twin-Telescope Binoculars

Signature T M J.B.L.

Date Late 1800s
Dimensions English Metric
Main Tube Length 6.1in 156mm
Main Tube Diameter (obj) 4.4in 112mm
Main Tube Diameter (eye) 1.1in 28mm
Extended Length 9.3in 235mm
Closed Length 1.3in 32mm
Inter-Pupilary Distance (min) 2.2in 55mm
Inter-Pupilary Distance (max) 2.7in 68mm
Objective Clear Aperture Diameter 1.3in 32mm


This pair of binoculars has tapered brass barrels, covered with brown leather. The objective lenses are achromatic doublets, contained in brass cells. It has long brass eyepiece tubes, four lens eyepieces, and flared hollow eyecups. The frame is hinged, so that the user can adjust for the distance between the eyes. On the middle cross piece of the frame there is a small scale, marked with gradations from 0 to 3, where this frame adjustment is indicated. Focusing is done with a central thumb wheel. All metal parts on the binoculars are brass, painted black.

"T M    J.B.L." is stamped on the face of both eyecups. These initials are not listed in the Webster Signature Database of makers. Between the T and M is a small logo, possibly a face with emanating rays.






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