Collection Home > Telescopes > Monocular-Single Draw > Ramsden Variable-Power Monocular
Ramsden Dual-Power Monocular
|Main Tube Length||1.7in||44mm|
|Main Tube Diameter||1.1in||27mm|
|Objective Clear Aperture Diameter||0.9in||23mm|
This monocular has a short round parallel silver-plated brass barrel. The objective lens is an achromatic doublet, mounted in a brass cell. It may not be original. It has one brass draw (without retention), two eye lenses, and a flared eyecup. The eye lenses are used one at a time by sliding a pin on the face of the eyecup to either position "1" or "2." These two lenses are mounted in a small metal plate inside the eyecup and pivot from one position to the other. There are two lines scribed around the draw also numbered "1" and "2." The eye lens and draw set at position "1" gives about 3X magnification and at position "2" about 6X magnification. When the sliding pin on the eyecup is set between "1" and "2" the eye lenses are covered. It is signed "Ramsden London" on the face of the eyecup. It comes with a case, covered with red leather.
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