Reflecting telescope

Essential information

Opening times: 
National Maritime Museum, First floor, The Great Map

This is a portable Gregorian (reflecting) telescope.

It is signed JAMES SHORT LONDON 128/832 = 12 meaning it has a focal length of 12 inches (304.8mm), and that James Short had made 128 of that size out of a total 832 telescopes by the time he made this one.

The barrel is made of brass. It has adjustable inclination and rotary movement. The eyepiece has a brass cap and there is a brass cap at the object end. Within the barrel are primary and secondary specula (mirrors).

There is a screw thread for focusing by moving the secondary mirror by use of the rod attached to the barrel. There is no finderscope but a sighting sytem instead. The telescope is in good condition. The length with the eyepiece is 525 mm, the diameter of the barrel is 85 mm, and the focal length is 304.8mm (12 inches).

The telescope is mounted on a pillar stand with three folding claw legs.