| RefNo | Title | Date |
| MC/4/97 | Letter from [Josiah] Forshall, [Secretary at the] British Museum, to Charles Richard Weld, [Assistant Secretary of the Royal Society] | 22 November 1845 |
| MC/1/195 | Letter from Josiah Forshall, [Secretary of the] British Museum, to the Society | 2 February 1830 |
| MC/2/225 | Letter from Josiah Forshall, [Keeper of the Manuscript department at the] British Museum, to John David Roberton, Assistant Secretary of the Royal Society | 15 October 1836 |
| MS/425/23 | Copy letter, John William Lubbock, Treasurer of the Royal Society, to [Josiah Forshall] the Secretary of the British Museum | 29 July 1831 |
| MS/426/59 | Copy letter from [Peter Mark] Roget, Secretary of the Royal Society; to Rev. [Josiah] Forshall, British Museum | 14 July 1842 |
| MS/123/10 | Letter from J[osiah] Forshall to the Duke of Sussex | 12 November 1832 |
| EC/1828/21 | Forshall, Josiah: certificate of election to the Royal Society | |
| MS/425/26 | Copy letter, John William Lubbock, Treasurer of the Royal Society, to [Josiah Forshall] the Secretary of the British Museum | 27 August 1831 |
| MC/2 | Volume 2 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1832-1838 |
| MC/1 | Volume 1 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1800-1831 |
| MC/4 | Volume 4 of miscellaneous correspondence regarding business matters, sent to the Royal Society | 1844-1850 |
| HS/27/65 | Letter, from Josiah Forshall to Sir John Herschel, dated at British Museum | 10 March 1848 |
| HS/27/63 | Draft letter, from Sir John Herschel to Josiah Forshall, dated at [Collingwood] | 14 July 1847 |
| HS/27/62 | Incomplete copy letter, from Sir John Herschel to [Josiah Forshall?], dated at 24 Berkeley Square | 9 June 1847 |
| HS/27/64 | Draft letter, from Sir John Herschel to [Josiah Forshall?], dated at 24 Berkeley Square | 9 June 1847 |