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Aluminum Twin Telescopes


Date Late 1800s
Dimensions English Metric
Closed Length 10.9in 277mm
Extended Length 15.4in 391mm
Main Tube Length 10.0in 254mm
Objective Clear Aperture Diameter 1.38in 35mm


This large pair of binoculars has parallel aluminum barrels, originally covered with leather. The objective lenses are achromatic doublets, contained in aluminum cells. It has long aluminum eyepiece tubes, four lens eyepieces, and flared eyecups. The thumbwheel with its axel perpendicular to the barrels adjusts the barrels' separation, to adjust for different eye spacing. The other thumbwheel, whose axel runs parallel to the barrels, is used for focusing. The objective lenses have extendable sunshades. Both the sunshade segments and the main barrels were originally covered in leather. The binoculars are not signed. A small star has been etched on one of the the objective tubes beneath the sunshade. The star also appears on an interior brass tube (of the same side) containing the field lens and eye lens.  


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