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Ramsden Library Telescope

Signature Je Ramsden , London

Date circa 1785
Number of Draws 1
Dimensions English Metric
Main Tube Length 25.8in 654mm
Main Tube Diameter 2.6in 65mm
Total Length 41.0in 1041mm
Closed Length 37.5in 953mm
Objective Clear Aperture Diameter 2.2in 57mm


This telescope has a round parallel lacquered brass barrel. The objective lens is an achromatic doublet with a push-on cap. It has a single brass draw with rack and pinion focusing by a thumbwheel. There is a separate terrestrial eyepiece tube, which screws into the collar at the end of the drawtube. It has four lenses and a slightly flared eyecup. The astronomical eyepiece tube is missing. It is boldly signed "Ramsden London" on the side of the barrel, with the eyepiece to the left. Within the "R" are the letters "Je", short for Jesse. The telescope is mounted on a folding brass cabriole tabletop stand, that has a stabilizing bar with a rack and pinion adjustment. It has a fitted mahogany case. Jesse Ramsden is considered to be one of the finest instrument makers of the late 1700s.


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