The University of Arizona
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Collapsible Galilean Binoculars

Signature BTE SGDG, France

Date Late 1800s
Dimensions English Metric
Main Tube Diameter 1.4in 35mm
Open Length 2.1in 54mm
Closed Length 4.4in 112mm
Inter-Pupilary Distance 2.5in 63mm
Objective Clear Aperture Diameter 1.2in 30mm


This pair of binocular opera glasses is unusual in that it collapses and stores as a single cylinder.  For storage, both eye lenses as well as the frame and focusing mechanism are inserted into the two barrels of the binoculars.  These two barrels then combine into a single cylinder.



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