All except (iii) are in Henry Mackenzie's handwriting. The contents are as follows. (i) Specimen of Henry Mackenzie’s writing “when at Mr Cossar’s writing school” (folio 2); (ii) ‘First Draught’ of the ‘last paper’ in the ‘Mirror’ (folio 3). See Henry Mackenzie’s ‘Collected works’, volume v, page 78. (iii) 'On the Succession of Minds' (folio 11). Above the title, in a modern hand, is pencilled '? Adam Smith No'. (iv) Draft of part of the life of John Home, author of 'Douglas' (folio 21); (v) Draft of a paper endorsed, “Character of Mr. Pitt and his Patriotic Exertions during the King’s Illness and towards the Close of his own Life. Query if adopted by Mr. G. Rose in his Pamphlet ? Yes ; vide his letter of 28 May 1806” (folio 25). See MS. 646, folio 41. (vi) Draft of a paper endorsed, “Introduction and Conclusion of Mr. George Rose’s Pamphlet ‘ Remarks on a portion of the History of G. Britain published by Mr. Fox ’” (Rose’s 'Observations on the historical work', etc., London, 1809) (folio 31). (vii) “Note as to Mr. Logan’s Poetical Works” (folio 48). Signed by Mackenzie