Register of nebulae by William Herschel and Caroline Herschel List of nebulae and star clusters, numbered 1501-2000, arranged in order of discovery, with all subsequent observations and descriptions of the astronomical objects. A fair copy and collated version of information gathered during telescopic sweeps of the night sky, made at Slough, Berkshire, England, generally with a reflecting telescope of 20 feet diameter and occasionally a 10 feet diameter instrument. These records were transcribed directly from the sweep books, usually on the day following the original sighting. Generally written on the recto sheets only. With occasional notes in pencil, some by John Frederick William Herschel. The wooden front board has a label: 'Sir William Herschel's nebulae No.1501 - ... - 2000'. 21 September 1786-4 February 1793