| RefNo | Title | Date |
| NLB/6/360 | Copy letter from Herbert Rix, to William Ellis, 1 Hyde Vale Villas, Greenwich, S.E. | 25 April 1892 |
| MC/15/278 | Letter from William Ellis, 1 Hyde Vale Villas, Greenwich, to Herbert Rix | 27 May 1892 |
| NLB/6/535 | Copy letter from Herbert Rix, to William Ellis, 1 Hyde Park Villas, Greenwich, S.E. | 30 May 1892 |
| NLB/11/32 | Copy letter from Theodore E James, to Messrs Harrison & Sons | [April 1895] |
| NLB/6/1018 | Copy letter from Herbert Rix, to William Ellis, 1 Hyde Vale Villas, Greenwich, S.E. | 4 October 1892 |
| NLB/16/740 | Copy letter from Robert William Frederick Harrison, to Messrs Harrison & Sons | 1 June 1898 |
| NLB/20/20 | Letter from an unknown correspondent, to Messrs Harrison & Sons | 16 January 1900 |
| NLB/32/608 | Copy letter from Robert William Frederick Harrison, to [Messrs Harrison & Sons] | [23 April 1906] |
| NLB/32/614 | Copy letter from Robert William Frederick Harrison, to William Ellis, Fellow of the Royal Society | 23 April 1906 |
| NLB/43/589 | Copy letter from Robert William Frederick Harrison, to [William] Ellis, Fellow of the Royal Society | 17 February 1911 |
| NLB/48/604 | Copy letter from Robert William Frederick Harrison, to William Ellis, Fellow of the Royal Society | 1 August 1913 |
| NLB/50/183 | Copy letter from Robert William Frederick Harrison, to [William] Ellis, Fellow of the Royal Society | 19 May 1914 |
| RR/8/156 | Referee's report by Balfour Stewart, on a paper 'On the relation between the diurnal range of magnetic declination and horizontal force, as observed at the Royal Observatory, Greenwich, during the years 1841 to 1877, and the period of solar spot frequency' by William Ellis | 12 June 1879 |
| RR/8/221 | Referee's report by William Thomson, Lord Kelvin, on a paper 'On the relation between the diurnal range of magnetic declination and horizontal force, as observed at the Royal Observatory, Greenwich, during the years 1841 to 1877, and the period of solar spot frequency' by William Ellis | 6 January 1880 |
| RR/11/146 | Referee's report by Joseph Norman Lockyer, on a paper 'On the simultaneity of magnetic variations at different places on occasions of magnetic disturbance, and on the relation between magnetic and earth current phenomena' by William Ellis | 1892 |
| IM/Maull/001296 | Ellis, William | nd |
| RR/17/37 | Referee's report by Thomas Edward Thorpe, on a paper 'A comparison of values of the magnetic elements, deduced from the British magnetic survey of 1891, with recent observation' by William Ellis | 3 December 1906 |
| NLB/28/446 | Copy letter from Robert William Frederick Harrison, to William Ellis, Fellow of the Royal Society | 7 March 1904 |
| EC/1893/04 | Ellis, William: certificate of election to the Royal Society | |
| RR/16/35 | Referee's report by William Ellis, on a paper 'An analysis of the results from the Kew Magnetographs on quiet days during the eleven years 1890-1900 etc.' by Charles Chree | 1 June 1903 |
| PP/20/17 | Paper, 'On the simultaneity of magnetic variations at different places on occasions of magnetic disturbance, and on the relation between magnetic and earth current phenomena' by William Ellis | 1892 |
| RR/6/316 | Letter from William Ellis, to George Gabriel Stokes, regarding a paper 'On the relation between the diurnal range of magnetic declination and horizontal force, as observed at the Royal Observatory, Greenwich, during the years 1841 to 1877, and the period of solar spot frequency' by William Ellis | 28 February 1880 |
| RR/11/145 | Referee's report by Arthur William Rucker, on a paper 'On the simultaneity of magnetic variations at different places on occasions of magnetic disturbance, and on the relation between magnetic and earth current phenomena' by William Ellis | 1 July 1892 |
| MC/15/279 | Letter from William Ellis, 1 Hyde Vale Villas, Greenwich, to [Herbert] Rix | 30 May 1892 |