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Other Ramsden Telescopes

 

Ramsden Three-Draw Telescope

Signature Ramsden, London

Date circa 1770
Dimensions English Metric
Main Tube Length 4.8in 122mm
Main Tube Diameter 1.4in 35mm
Total Length 14.5in 368mm
Closed Length 5.2in 132mm
Objective Clear Aperture Diameter 1.2in 30mm

Description

This telescope has a round parallel barrel (probably mahogany) with a push-on objective lens cap.  The objective is a single double-convex lens and both the lens and its copper-colored cell appear to be replacements.  The original lens was in all probability an achromatic doublet.  It has three brass draws, a four lens eyepiece, and a flared eyecup with a swivel cover.  The screw holding the cover to the eyecup has been replaced.  It is signed "Ramfden London" (f is an Old English version of s) on the eyepiece draw, with the eyecup to the left.

 


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