Letter listing for 1820–1829
- John Phillips to Reverend William Venables Vernon Harcourt, 3 January 1826
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, 1 February 1826
- Clara Mary Jane Clairmont to Mary Wollstonecraft Shelley [née Godwin], 14 May 1826
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, 8 August 1826
- Sir John Frederick William Herschel, 1st baronet of Slough to Caroline Lucretia Herschel, 17 September 1826
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, 29 September 1826
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, 1 November 1826
- Clara Mary Jane Clairmont to Jane Johnson [née Cleveland], December 1826
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, 5 December 1826
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, 24 December 1826
- Henry Peter Brougham, 1st Baron Brougham and Vaux to Sir David Brewster, 1827
- Reverend William Venables Vernon Harcourt to Reverend Adam Sedgwick, 13 March 1827
- Reverend Adam Sedgwick to Reverend William Venables Vernon Harcourt, 15 March 1827
- Caroline Lucretia Herschel to Sir John Frederick William Herschel, 1st baronet of Slough, April 1827
- Sir John Frederick William Herschel, 1st baronet of Slough to Caroline Lucretia Herschel, 4–11 May 1827