Notebook, paper with leather-covered card covers, notebook of John Harrison, Peterborough, 3 February 1864. Appears to be a railway engineer's commonplace book. Includes rules for solving problems with safety valves, experiments on pressure gauge accuracy in various locomotives, calculations on horsepower, notes on various pumping engines, notes on materials, specification of a six-wheeled coupled goods engine, etc. Some of the entries note their sources. Notebook of John Harrison