The collection, 1735-1778, comprises a 'short account' of Howell Harris's life, a long series of diaries, 1735-1772, memoranda, 'observations' and notes, prayers, a few letters, a note, 1742, on the differences between Howell Harris (and John Whitefield) and John Wesley, a statement, 1744, on Harris's intended marriage, extracts from diaries, spiritual observations, minutes of associations, miscellaneous memoranda and receipts, and a series of notes relating to 'affairs at Trevecka'.