'Daguerreotype passe-partout of Dr Herschel', c 1850.

A daguerreotype of William Herschel (1738-1822), copied from an engraving by James Godby of a portrait by Rehberg, from 1814, taken by an unknown photographer in about 1850. Sir William Herschel was probably the most famous astronomer of the 18th century. Among many of his important findings, he discovered the planet Uranus in 1781. At his family home, Observatory House, Slough, Herschel had the largest reflecting telescope in the world. It was 40 feet long with a 48-inch mirror. He and his sister Caroline (1750-1848) were devoted to cataloguing their discoveries and were also both dedicated musicians.