These letters range from a criticism of Manning';s mathematical work to a family friend writing to William Manning regarding his concern of Thomas Manning's plan to visit China. Of particular note is a draft letter from Manning to Joseph Banks outlining the route of his Chinese studies and plans to travel to China.

Thomas Manning was an inveterate note-taker, making notes about all aspects of knowledge that interested him. These notes and notebooks cover from his early mathematical and poetical musing, through his travels in China and Tibet to later concerns regarding Roman Catholic emancipation. They have been organised into various sections mainly according to their subject manner.Thus:

• TM/9/1: Notebook with inserts from time at university to later life and covering all topics.
• TM/9/2 - 5 A series of notebooks from Manning's time in China and Tibet including notes on his travels and language studies
• TM/9/6 Loose notes from Chinese period
• TM/9/7 Pocket almanacs with annotations
• TM/9/8 Poetry and Riddles
• TM/9/9 Mathematical Notes and Notebooks
• TM/9/10 Notes on Roman Catholic Emancipation

Notebook with mathematical notes, diagrams and problems. Also contains draft of a [story] and doodles of a face. Handwritten in blue covered notebook, writing begins at both ends of the book. Loose sheet is headed "Prop. 1, June 19th 1800" with mathematical proposition written in Latin

Notebook with mathematical notes, diagrams and problems. Also contains philosophical musings on man and war, geometrical drawings, notes on Chinese words, diagram for creating a weigh balance, instructions to extract salt and draft lines for a poem. Handwritten in a blue paper cover notebook written from both ends. Reverse cover is missing. Cover states "Some philosophical observations in this book".