|Place of work||Greenwich|
||1 or 2 Aug 1841 – Mar 1852 & May/Jun 1853 – 31 Dec 1893|
|Posts||1841, Aug 1 or 2
||Computer, Planetary and Lunar Reductions
|1848, Jun 1||Computer in the Astronomcial Branch|
||To Durham University Observatory as Assistant|
|1853, Jun 1?
|1871, Apr 1
||First Class Assistant (following regrading exercise)|
|Born||1828, Feb 20
|Died||1916, Dec 11
|Family Links||Father Thomas Ellis, Assistant, 1825–1852|
|Known Addresses||1845–1852||? living with his parents at 6 Cottage Place (renamed c.1899 as 65 Dutton Street)|
|1870–1872||25 Prior Street|
|1872–1878||88 London Street. Renamed as 205 Greenwich High Road in the 1930s|
|1885–1894||1 Hyde Vale Villas (now 28 Hyde Vale)|
|1895–1904||12 Vanburgh Hill|
|1906–1916||78 Coleraine Road Blackheath|
Ellis started work as a Boy Computer at the age of 13 in August 1841. Initially he worked on the Planetary and Lunar Reductions, a body of work that was separately funded by the Treasury, but took place under Airy’s supervision at Greenwich. In 1845, he commenced observing duties. He was later transferred to the Astronomical Branch of the Observatory (in June 1848?), where he continued with his observing duties (except in the year 1848 itself). In 1852, Airy recommended him as a suitable candidate to replace Richard Carrington as Assistant at the Durham University Observatory. Having accepted the post, he wasn’t in Durham very long, before there were two deaths in quick succession amongst the Assistants at Greenwich: first of all his father on 29 May 1852 and then William Rogerson on 26 April 1853. Rogerson’s post was offered to Ellis who appears to have commenced his duties as an Assistant at Greenwich at the start of June 1853 (Laurie gives the date as 13 May 1853 in the Complete Dictionary of Scientific Biography – of which the online version carries an image of an entirely different William Ellis). Following the tendering of Hugh Breen’s letter of resignation as Fourth Assistant at the end of 1858 , examinations for promotion to and within the Assistant Grade (for trial of competency) began for the first time. At that time, the first four Assistants were regarded as senior and all were on different rates of pay. The other three Assistants (Ellis, Criswick and Lynn) were regarded as junior and were all paid the same rate of £100 a year irrespective of their length of service. Of the three, Ellis had been at the Observatory the longest. He took the exam set by Airy and was promoted to Fourth Assistant on 1 Feb 1859 on a salary of £150 a year. He was the first and last of the Assistants to take an exam in order to receive an increase in pay. His examination script is preserved in the archives at Cambridge (RGO6/4). When a new staffing structure and pay scales were introduced in 1871, Ellis was regraded as a First Class Assistant.
When first appointed as an Assistant, Ellis became on of the four regular observers with the Transit Circle and Altazimuth Instrument. Following the departure of Charles Todd for Australia in 1855, Ellis took on responsibility for the galvanic systems (the chronographs and time signals). When John Henry Belville died in 1856, he also took on responsibility for the chronometers being head of what was effectively a newly created Time Department. When Glaisher resigned his position as Superintendent of the Magnetical and Meteorological Department at the end of 1874, Ellis asked if he could take on the roll. He became the Department’s new Superintendent at the start of 1875, continuing in the post until his retirement at the end of 1893.
Between them, William Ellis and his father served the Observatory for a period of nearly 70 years. His death in 1916 severed a remarkable link dating back to the time of John Pond. In retirement, he lived at 12 Vanburgh Hill, just a couple of doors along from Frank Dyson who was appointed to the post of Chief Assistant in 1894. Ellis was twice married, but had no children. He married his first wife Sarah Campion in 1869. After she died in 1906, he married a distant cousin, Margaret Ellis who like his father came from Yorkshire.
On the ocassion of Ellis’s 85th birthday, a group photograph was taken outside the old Magnetic Pavillion where the Peter Harrison Planetarium now stands. A copy is held by the National Maritime Museum. The archives at Cambridge also have an undated photo in RGO 54/4.