Bestanddeel TM/9/9/2 - Notebook with mathematical notes, diagrams and problems

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".