| Reference number | Title | Date |
| EC/1881/17 | Preece, Sir William Henry: certificate of election to the Royal Society | |
| MS/743/1/103 | Letter from William Henry Preece, Post Office, London, to [John Hall Gladstone] | 12 October 1882 |
| IM/Maull/003649 | Preece, Sir William Henry | nd |
| IM/000091 | Preece, Sir William Henry | 1889 |
| NLB/2/77 | Copy letter from Herbert Rix, to John William Strutt, 3rd Baron Rayleigh | 6 January 1888 |
| NLB/2/242 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 9 March 1888 |
| NLB/2/184 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 15 February 1888 |
| NLB/2/624 | Copy letter from Herbert Rix, to Mr William Henry Preece, Fellow of the Royal Society | 28 September 1888 |
| NLB/4/448 | Copy letter from Herbert Rix, to Mr William Henry Preece | 4 June 1890 |
| NLB/3/209 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 10 April 1889 |
| NLB/4/618 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 23 July 1890 |
| NLB/4/627 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 25 July 1890 |
| NLB/4/777 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 25 October 1890 |
| NLB/7/930 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 28 May 1893 |
| NLB/6/412 | Copy letter from Herbert Rix, to Mr William Henry Preece | 6 May 1892 |
| NLB/6/594 | Copy letter from Herbert Rix, to Mr William Henry Preece | 8 June 1892 |
| NLB/6/463 | Copy letter from Herbert Rix, to L Pyke, 34 New Tothill Street, Westminster | 17 May 1892 |
| NLB/6/430 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 10 May 1892 |
| NLB/3/991 | Copy letter from Herbert Rix, to Messrs Gordon & Hollands, Hotel Metropole | 3 December 1889 |
| NLB/3/1016 | Copy letter from Herbert Rix, to Mr William Henry Preece | 12 December 1889 |
| NLB/5/440 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 11 June 1891 |
| NLB/5/522 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 7 July 1891 |
| NLB/7/713 | Copy letter from Theodore E James, to William Henry Preece, Fellow of the Royal Society | 13 April 1893 |
| NLB/7/830 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 5 May 1893 |
| NLB/10/469 | Copy letter from Herbert Rix, to Willilam Henry Preece, Fellow of the Royal Society | 28 November 1894 |
| NLB/9/130 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 4 April 1894 |
| NLB/11/107 | Copy letter from Herbert Rix, to Professor William Chandler Roberts-Austen, Fellow of the Royal Society | 22 April 1895 |
| NLB/11/116 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 24 April 1895 |
| NLB/13/203 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society | 1 July 1896 |
| NLB/9/704 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society, Engineer's Department, General Post Office, E.C. | 2 July 1894 |
| NLB/19/125 | Copy letter from Theodore E James, to Messrs Harrison & Sons | 27 June 1899 |
| NLB/13/86 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society, Telegraph Department, General Post Office, E.C. | 8 June 1896 |
| NLB/14/579 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society | 1 April 1897 |
| NLB/12/768 | Copy letter from Theodore E James, to William Henry Preece, Fellow of the Royal Society | 29 April 1896 |
| NLB/14/91 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society | 4 January 1897 |
| NLB/14/790 | Copy letter from Robert William Frederick Harrison, to J Hookey, Telegraph Department, Post Office | 17 May 1897 |
| NLB/14/781 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society | 14 May 1897 |
| NLB/14/890 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society | 1 June 1897 |
| NLB/20/62 | Copy letter from Michael Foster, to Professor William Henry Preece | 25 June 1900 |
| NLB/16/520 | Copy letter from Robert William Frederick Harrison, to W H Preece, Fellow of the Royal Society | 26 April 1898 |
| NLB/16/657 | Copy letter from Theodore E James, to W H Preece, Fellow of the Royal Society | 18 May 1898 |
| NLB/17/44 | Copy letter from Arthur William Rucker, to William Henry Preece, Fellow of the Royal Society | 7 July 1898 |
| NLB/16/721 | Copy letter from Robert William Frederick Harrison, to W H Preece, Fellow of the Royal Society, Telegraph Department, General Post Office | 25 May 1898 |
| NLB/16/720 | Copy letter from Robert William Frederick Harrison, to R Stewart Bain, Manager, London Electric Supply Corporation, 25a Cockspur Street, S.W. | 25 May 1898 |
| NLB/17/132 | Copy letter from Arthur William Rucker, to William Henry Preece, Fellow of the Royal Society | 23 July 1898 |
| NLB/16/764 | Copy letter from Robert William Frederick Harrison, to Francis Fox, Alyn Bank, Wimbledon, S.W. | 2 June 1898 |
| NLB/19/139 | Copy letter from Arthur William Rucker, to William Henry Preece, [Fellow of the Royal Society] | 28 June 1899 |
| NLB/18/304 | Copy letter from Robert William Frederick Harrison, to W H Preece, Fellow of the Royal Society | 20 February 1899 |
| NLB/19/82 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society | 15 June 1899 |
| NLB/17/631 | Copy letter from Robert William Frederick Harrison, to William Henry Preece, Fellow of the Royal Society | 28 November 1898 |
| NLB/20/41 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society | 20 January 1900 |
| NLB/18/703 | Copy letter from Arthur William Rucker, to [Professor G C] Foster | 26 April 1899 |
| NLB/22/309 | Copy letter from Robert William Frederick Harrison, to Sir William [Henry] Preece, Fellow of the Royal Society, Gothic Lodge, Wimbledon | 19 April 1901 |
| NLB/22/542 | Copy letter from Robert William Frederick Harrison, to Sir William [Henry] Preece, Fellow of the Royal Society | 31 May 1901 |
| NLB/26/547 | Copy letter from Robert William Frederick Harrison to, Sir William Preece, Fellow of the Royal Society | 8 April 1903 |
| NLB/26/262 | Copy letter from Robert William Frederick Harrison to, Sir William Henry Preece, Fellow of the Royal Society | 19 February 1903 |
| NLB/27/63 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society | 25 June 1903 |
| NLB/27/5 | Copy letter from Joseph Larmor, to Sir William Preece, [Fellow of the Royal Society] | 15 June 1903 |
| NLB/26/485 | Copy letter from Robert William Frederick Harrison to, Sir William Henry Preece, Fellow of the Royal Society | 30 March 1903 |
| NLB/29/748 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society, 8 Queen Anne's Gate, Westminster, S.W. | 5 December 1904 |
| NLB/33/280 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society, Gothic Lodge, Wimbledon | 27 July 1906 |
| NLB/34/417 | Copy letter from Joseph Larmor, to Sir William Henry Preece, Fellow of the Royal Society | 17 January 1907 |
| NLB/36/391 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society | 24 October 1907 |
| NLB/37/826 | Copy Letter from Robert William Frederick Harrison to Professor F [Francis] W [Wall] Oliver, Fellow of the Royal Society | 20 May 1908 |
| NLB/37/829 | Copy Letter from Robert William Frederick Harrison to Sir William Preece, KCB, Fellow of the Royal Society | 20 May 1908 |
| NLB/37/844 | Copy Letter from Robert William Frederick Harrison to Sir William H [Henry] Preece, KCB, FRS | 22 May 1908 |
| NLB/41/120 | Copy letter from Robert William Frederick Harrison, to Sir William Henry Preece, Fellow of the Royal Society | October 1909 |
| RR/14/16 | Letter from Willard E Case, to William Henry Preece, regarding a paper 'On the oxidation of carbon at ordinary temperatures' by Willard E Case | 9 June 1898 |
| RR/10/371 | Referee's report by Joseph John Thomson, on a paper 'On the heating effects of electric currents' by William Henry Preece | 1 July 1890 |
| RR/9/178 | Third referee's report by Augustus George Vernon Harcourt, on a paper 'On a new standard of illumination and the measurement of light' by William Henry Preece | 18 July 1883 |
| RR/9/179 | Referee's report by William de Wiveleslie Abney, on a paper 'On a new standard of illumination and the measurement of light' by William Henry Preece | 21 July 1883 |
| RR/9/177 | Second referee's report by Augustus George Vernon Harcourt, on a paper 'On a new standard of illumination and the measurement of light' by William Henry Preece | 10 July 1883 |
| NLB/8/800 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 1 January 1894 |
| NLB/2/792 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 7 November 1888 |
| NLB/11/108 | Copy letter from Herbert Rix, to William Henry Preece, Fellow of the Royal Society | 22 April 1895 |
| NLB/13/21 | Copy letter from Robert William Frederick Harrison, to Professor Michael Foster, Secretary, Royal Society | 29 May 1896 |
| RR/10/250 | Referee's report by William Henry Preece, on a paper 'On the effect of temperature on the specific inductive capacity of a dielectric' by W Cassie | 10 July 1889 |
| RR/9/176 | Referee's report by Augustus George Vernon Harcourt, on a paper 'On a new standard of illumination and the measurement of light' by William Henry Preece | 9 July 1883 |
| MC/12/42 | Letter from W H [William Henry] Preece, General Post Office, to W [William] E Spottiswoode, [President of the Royal Society] | 27 April 1880 |
| MC/12 | Volume 12 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1880-1883 |
| AP/66/25 | Unpublished paper, 'On the heating effects of electric currents, no. IV' by William Henry Preece | 1890 |
| PP/3/24 | Paper, 'The effects of temperature on the electromotive force and resistance of batteries' by W H [William Henry] Preece | 1883 |
| AP/66/15/1 | Unpublished manuscript, 'Experiments on the resistance of electrolytic cells' by H R Sankey | 1889 |
| AP/66/15 | Unpublished paper, 'Experiments on the resistance of electrolytic cells' by H R Sankey | 1889 |
| AP/74/7 | Unpublished paper, 'The oxidation of carbon at ordinary temperature by means of atmospheric oxygen with the production of electrical energy' by Willard [Erastus] Case | 1899 |
| AP/74/7/1 | Unpublished manuscript, 'The oxidation of carbon at ordinary temperature by means of atmospheric oxygen with the production of electrical energy' by Willard [Erastus] Case | 1899 |
| PP/6/33 | Paper, 'On charging secondary batteries' by W H [William Henry] Preece | 1885 |
| PP/3/7 | Paper, 'The influence of heat on the galvanic elements' by William Henry Preece | [1883] |
| PP/6/25 | Paper, 'On a peculiar behaviour of glow-lamps when raised to high incandescence' by W H [William Henry] Preece | 1885 |
| PP/4/24 | Paper, 'On a new standard of illumination and the measurement of light' by W H [William Henry] Preece | 1883 |
| PP/4/24/2 | Diagrams, experimental equipment by W H [William Henry] Preece | 1883 |
| PP/4/42 | Paper, 'On the heating effects of electric currents' by W H [William Henry] Preece | 1884 |
| PP/4/42/1 | Manuscript, 'On the heating effects of electric currents' by W H [William Henry] Preece | 1884 |
| PP/4/42/2 | Diagrams, experimental equipment and results by W H [William Henry] Preece | 1884 |
| PP/6/25/1 | Manuscript, 'On a peculiar behaviour of glow-lamps when raised to high incandescence' by W H [William Henry] Preece | 1885 |
| PP/6/25/2 | Figures, experimental equipment and results by W H [William Henry] Preece | 1885 |
| PP/6/33/1 | Manuscript, 'On charging secondary batteries' by W H [William Henry] Preece | 1885 |
| PP/6/33/2 | Diagrams, experimental equipment and results by W H [William Henry] Preece | 1885 |
| PP/8/24 | Paper, 'On a new means of converting heat energy into electrical energy' by Williard E [Erastus] Case | 1886 |
| PP/8/32 | Paper, 'On a new scale for tangent galvanometers' by W H [William Henry] Preece and H R Kempe | 1886 |
| PP/8/32/1 | Manuscript, 'On a new scale for tangent galvanometers' by W H [William Henry] Preece and H R Kempe | 1886 |
| PP/8/32/2 | Diagrams, tangent galvanometer scale by W H [William Henry] Preece and H R Kempe | 1886 |
| PP/10/17 | Paper, 'On the limiting distance of speech by telephone' by W H [William Henry] Preece | 1887 |
| PP/12/3 | Paper, 'On the heating effects of electric currents. No. III' by W H [William Henry] Preece | 1888 |
| PP/11/14 | Paper, 'On the heating effects of electric currents. No II' by W H [William Henry] Preece | 1887 |
| PP/4/24/1 | Manuscript, 'On a new standard of illumination and the measurement of light' by W H [William Henry] Preece | 1883 |
| PP/15/10 | Paper, 'On electric discharge between electrodes at different temperatures in air and in high vacua' by J A [John Ambrose] Fleming | 1889 |
| MC/23/85 | Letter from [Sir William Henry] Preece, 8 Queen Anne's Gate, London, to [Robert] Harrison, The Royal Society | 21 December 1908 |
| MC/23/88 | Letter from [Sir William Henry] Preece, 8 Queen Anne's Gate, Westminster, to Robert Harrison, [The Royal Society] | 28 May 1908 |
| MC/23/86 | Letter from [Sir William Henry] Preece, 8 Queen Anne's Gate, Westminster, to Robert Harrison, [The Royal Society] | 21 May 1908 |
| MC/23/87 | Letter from [Sir William Henry] Preece, 8 Queen Anne's Gate, Westminster, to Robert Harrison, [The Royal Society] | 19 May 1908 |
| MC/23/84 | Telegram from Mr Case, forwarded by Sir William Preece, to Sir Archibald Geikie, Secretary of The Royal Society | 22 May 1908 |
| MC/23/443 | Letter from [George J] Stevens, 25 Eastlake [Road], London SE, to [Robert] Harrison, Assistant Secretary, [Royal Society] | 8 July 1908 |
| MC/24/117 | Letter from [William Henry] Preece, Gothic Lodge, Wimbledon Common, to Mr [Robert] Harrison, [Royal Soicety] | 11 February 1909 |
| MC/17 | Volume 17 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1897-1899 |
| MC/23 | Volume 23 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1908 |
| MC/21 | Volume 21 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1906 |
| MC/21/507 | Letter from William Henry Preece, 8 Queen Anne's Gate, Westminster, to the Secretary of the Royal Society | 8 May 1906 |