| RefNo | Title | Date |
| NLB/54/531 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to [Messrs Harrison & Sons] | 11 June 1917 |
| IM/Maull/002296 | Hughes, Thomas McKenny | nd |
| NLB/7/411 | Copy letter from Herbert Rix, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 10 February 1893 |
| NLB/8/414 | Copy letter from the Assistant Secretary [Herbert Rix], to Messrs Harrison & Sons | 23 October 1893 |
| NLB/9/461 | Copy letter from Herbert Rix, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 22 May 1894 |
| NLB/11/403 | Copy letter from Herbert Rix, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 21 June 1895 |
| NLB/14/831 | Copy letter from Robert William Frederick Harrison, to Sir Archibald Geikie, Fellow of the Royal Society | 26 May 1897 |
| NLB/14/822 | Copy letter from Robert William Frederick Harrison, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 25 May 1897 |
| NLB/14/838 | Copy letter from Robert William Frederick Harrison, to the Under Secretary of State for Foreign Affairs, The Foreign Office, Downing Street, S.W. | 26 May 1897 |
| NLB/19/11 | Copy letter from Robert William Frederick Harrison, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 2 June 1899 |
| NLB/19/91 | Copy letter from Robert William Frederick Harrison, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 17 June 1899 |
| NLB/23/2/47 | Copy letter from Sir Michael Foster, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 26 March 1901 |
| NLB/23/2/419 | Copy letter sent from unknown correspondent, to Professor McKenny Hughes, Fellow of the Royal Society | 14 December 1903 |
| NLB/23/2/414 | Copy letter sent from Joseph Larmor, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 11 December 1903 |
| NLB/23/1/759 | Copy letter from Robert William Frederick Harrison, to Professor Thomas McKenny Hughes, Fellow of the Royal Society | 17 January 1902 |
| NLB/28/60 | Copy letter from [Theodore E James], to [Messrs Harrison & Sons] | 4 January 1904 |
| NLB/27/697 | Copy letter from Robert William Frederick Harrison, to Thomas McKenny Hughes, Fellow of the Royal Society | 14 November 1903 |
| NLB/27/656 | Copy letter from Robert William Frederick Harrison, to Professor Thomas McKenny Hughes, Fellow of the Royal Society, Woodwardian Museum, Cambridge | 10 November 1903 |
| NLB/40/571 | Copy letter from Robert William Frederick Harrison to Professor T [Thomas] McKenny Hughes FRS | 29 June 1909 |
| NLB/54/580 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to Sir Archibald Geikie, FRS | 25 June 1917 |
| NLB/53/84 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to Professor [Thomas] McKenny Hughes, FRS | Undated |
| MC/32/100 | Letter from [Archibald] Geikie, Shepherd's Down, Haslemere, Surrey, to Mr [Robert] Harrison, [Royal Society] | 30 June 1917 |
| EC/1889/12 | Hughes, Thomas McKenny: certificate of election to the Royal Society | |
| MC/14/47 | Letter from Thomas McKenny Hughes, Cambridge, to [Thomas George] Bonney | 13 June 1885 |
| MC/16/225 | Letter from [Thomas] McKenny Hughes, 18 Hill Road, Cambridge, to [John] Evans | 7 June 1895 |
| MC/16 | Volume 16 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1893-1896 |
| MC/16/226 | Letter from [Thomas] McKenny Hughes, 18 Hill Road, Cambridge, to Lord Kelvin [William Thomson] | 7 June 1895 |