The archives at Chatsworth include the correspondence of Georgiana, Duchess of Devonshire and her mother Lady Spencer, comprising some 1180 letters by Georgiana (many of them written in the form of a journal) and the letters by Lady Spencer to Georgiana; together with the journals of Lady Spencer from 17 September 1764 to 4 October 1793. This group constitutes the single most important primary source for the life of the Duchess.
These two letters are from Georgiana to Lady Elizabeth Foster, the mistress of the 5th Duke with whom she nevertheless shared a great friendship. The duchess's letters, in style and script, were wholly individual, vividly reflecting the dramatic tone and events of her life. The gambling debts that beset her were thus confessed to Lady Elizabeth Foster:
'At length my ever ever Dearest Bess, I am going to reveal the long kept secret from you - I should have told you sooner but I knew the very mention of my having been distressd about such a thing as money wd have allarm'd you...
...Before I say a word more you must promise my very Dearest Dearest Dst angelic Love never to let Canis [their shared nickname for the 5th Duke] know I have told this secret to you..'