Paper, 'A summary account and abstract of some of new inventions and improvements, relating to mechanicks and hydraulicks, containd in the following propositions and problems; to demonstrate the solution wherof particular draughts and medells, with a description thereof have been prepared' by David Stephenson Stephensondiscusses generating motion, power, and force in solid objects and fluids, producing power from centrifugal force, reducing friction in engines, capturing animal, wind, and water energy, and creating hydraulic engines. Subject: Engineering / Mechanics Read to the Royal Society on 6 November 1740 1740