The University of Arizona
College of Optical Sciences

Collection Home > Telescopes >Multiple-Draw > Ramsden Three-Draw

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


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.


College of Optical Sciences
The University of Arizona, 1630 East University Boulevard, Tucson, Arizona U.S.A. 85721-0094

All contents copyright 2008  Arizona Board of Regents.