Herschel 20-Foot Telescope
This long wooden tube is from William Herschel's 20-foot telescope. He began observing with the telescope in 1783, and though he went on to build even larger ones, his 20-foot remained his favorite. In 1820 Herschel and his son John rebuilt the telescope, which had deteriorated after decades of use, salvaging what they could from the original. The tube displayed here is a product of that reconstruction.
Lent by the National Maritime Museum, London Image Courtesy of the Royal Astronomical Society