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Decagonal Reverse Taper Telescope

Signature Dollond, London


Date Late 1700s
Dimensions English Metric
Main Tube Length 23.9in 607mm
Main Tube Diameter (objective end) 1.5in 38mm
Main Tube Diameter (eyepiece end) 1.7in 42mm
Total Length 33.0in 838mm
Closed Length 25.0in 635mm
Objective Diameter 0.9in 24mm


This telescope has a decagonal mahogany barrel, painted dark red. It has a very slight reverse taper - the objective end of the barrel is smaller than the eye-tube end. The objective lens is an achromatic doublet with a push-on lens cap. It has a single brass segmented draw (without retention), a five lens eyepiece, and a flared eyecup with a swivel cover. It is signed "Dollond London" on the draw, with the eyecup to the right.  It is very unusual for an achromatic telescope to have a reverse taper.



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