BATH.- The Herschel Museum of Astronomy revealed the display of a new object: a Gregorian Reflector telescope created by James Short, the pre-eminent telescope maker of the 18th century. The telescope, which is on long-term loan to the Herschel Museum of Astronomy from Richard N. Blythe of Shropshire, was created between 1738-1768, and is an excellent example of its kind.

The brass telescope has a focal length of 18 inches, and sits on an equatorial mount. Similar telescopes made by Short were used to observe the transit of Venus in 1761 and 1769.

Gregorian Reflector telescopes are constructed with two concave mirrors. The primary mirror collects incoming light and brings it to a focal point. Subsequently, this focused light is reflected off the secondary mirror, after which the light passes through a central aperture within the primary mirror. Ultimately, it emerges from the bottom of the instrument, facilitating observation through the eyepiece.

In his 30-year career Short made at least 1300 telescopes and they were considered the finest available, sought after by observatories and customers all over the world. Short had no assistant and when he died in 1768 his method of polishing mirrors was lost. Separately, William Herschel started experimenting with making telescopes in 1773 and he went on to create telescopes of even greater quality than Short.

Patrizia Ribul, Director of Museums for Bath Preservation Trust says: “The story of the Herschel siblings William and Caroline is very special, and our acquisitions policy is focused on objects that either belonged to them, or that add important context from the time. The James Short telescope provides visitors with an excellent example of the type of telescope that would have been known to William Herschel. The fact that William, with Caroline’s assistance, went on to create telescopes superior even to this excellent example by James Short, really underlines his expertise and dedication in the field of astronomy.”

The James Short telescope is the latest in a line of exciting long-term loans and acquisitions at the museum, which also include Caroline Herschel’s visitor book, a full-sized replica of Herschel's seven-foot reflecting telescope, and Caroline Herschel’s original memoir manuscript.