| RefNo | Title | Date |
| EC/1891/11 | Gilchrist, Percy Carlyle: certificate of election to the Royal Society | |
| IM/001653 | Gilchrist, Percy Carlyle | nd |
| MC/19/331 | Letter from Percy [Carlyle] Gilchrist, France, to the Assistant Secretary of the Royal Society, London | 4 December 1904 |
| NLB/13/580 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society, Frognal Bank, Finchley Road, Hampstead, N.W. | 10 October 1896 |
| NLB/5/1118 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 6 January 1892 |
| NLB/5/1258 | Copy letter from Herbert Rix, to Professor Percy Carlyle Gilchrist, Fellow of the Royal Society | 5 February 1892 |
| NLB/5/1093 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 4 January 1892 |
| NLB/10/475 | Copy letter from Herbert Rix, to Messrs Harrison & Sons | 4 December 1894 |
| NLB/10/420 | Copy letter from Herbert Rix, to Professor Michael Foster | 21 November 1894 |
| NLB/9/383 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 9 May 1894 |
| NLB/10/479 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 4 December 1894 |
| NLB/10/1 | Copy letter from A H White, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 17 August 1894 |
| NLB/10/433 | Copy letter from Herbert Rix, to Professor William Chandler Roberts-Austen | 23 November 1894 |
| NLB/10/488 | Copy letter from Theodore E James, to Messrs Harrison & Sons | 4 December 1894 |
| NLB/8/661 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 5 December 1893 |
| NLB/10/432 | Copy letter from Herbert Rix, to Professor Michael Foster | 23 November 1894 |
| NLB/9/286 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 16 April 1894 |
| NLB/9/369 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 26 April 1894 |
| NLB/9/436 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 18 May 1894 |
| NLB/9/521 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 31 May 1894 |
| NLB/9/470 | Copy letter from Herbert Rix, to Percy Caryle Gilchrist, Fellow of the Royal Society | 23 May 1894 |
| NLB/9/718 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society, Frognal Bank, Finchley Road, Hampstead, N.W. | 5 July 1894 |
| NLB/9/716 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 5 July 1894 |
| NLB/9/331 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 30 April 1894 |
| NLB/17/296 | Copy letter from Robert William Frederick Harrison, to Percy Caryle Gilchrist, Fellow of the Royal Society, Frognal Bank, Finchley Road, Hampstead, N.W. | 6 October 1898 |
| NLB/13/610 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 15 October 1896 |
| NLB/14/92 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 4 January 1897 |
| NLB/29/791 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 12 December 1904 |
| NLB/18/169 | Copy letter from Robert William Frederick Harrison, to P C Gilchrist, Fellow of the Royal Society | 30 January 1899 |
| NLB/17/286 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society, Frognal Bank, Finchley Road, Hampstead, N.W. | 3 October 1898 |
| NLB/18/827 | Copy letter from Theodore E James, to Messrs Harrison & Sons | 29 May 1899 |
| NLB/19/724 | Copy letter from Robert William Frederick Harrison, to Messrs Harrison & Sons | 3 December 1899 |
| NLB/20/73 | Copy letter from Theodore E James, to Messrs Harrison & Sons | 26 January 1900 |
| NLB/32/386 | Copy letter from Robert William Frederick Harrison, to [Messrs Harrison & Sons] | 2 March 1906 |
| NLB/29/755 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 6 December 1904 |
| NLB/33/301 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society, Baschurch, Salop | 31 July 1906 |
| NLB/29/817 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 14 December 1904 |
| NLB/32/366 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 27 February 1906 |
| NLB/33/522 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 21 September 1906 |
| NLB/33/230 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society, Baschurch, Salop | 20 July 1906 |
| NLB/32/549 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 31 March 1906 |
| NLB/33/276 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Socity, Baschurch, Salop | 27 July 1906 |
| NLB/33/532 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society, Baschurch, Salop | 24 September 1906 |
| NLB/35/28 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 5 April 1907 |
| NLB/34/276 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 20 December 1906 |
| NLB/34/688 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 26 February 1907 |
| MC/19/332 | Letter from Percy [Carlyle] Gilchrist, France, to the Assistant Secretary of the Royal Society | 12 December 1904 |
| NLB/46/110 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 11 June 1912 |
| NLB/52/197 | Copy letter from [Robert William Frederick Harrison, Assistant Secretary of the Royal Society]; to Publications, The Royal Society | 12 October 1915 |
| NLB/9 | New Letter Book volume 9, copy letters sent from Royal Society administration | 8 March-17 August 1894 |
| NLB/9/223 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 18 April 1894 |
| NLB/9/463 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Frognal Bank, Finchley Road, Hampstead, N.W. | 22 May 1894 |
| NLB/9/368 | Copy letter from Herbert Rix, to Percy Carlyle Gilchrist, Fellow of the Royal Society, 101 Palace Chambers, Westminster | 7 May 1894 |
| NLB/13/645 | Copy letter from Robert William Frederick Harrison, to Percy Carlyle Gilchrist, Fellow of the Royal Society | 23 October 1896 |
| MC/19 | Volume 19 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1904 |