The fire pump of Ktesibios and Heron

It was a twin suction force piston pump of continuous water flow that was used for firefighting and continued identically having the same use until recently. It consisted of two pistons that reciprocated oppositely with the help of a pivoted common hand lever within two vertical cylindrical containers immersed in the (probably wheeled) water tank. The non-return valves of the incoming water were in the raised bottom of the containers and the non-return outlet valves were at the base of the discharge pipes. The pipes converged to a common vertical pipe. At the end of the pipe there was an ingenious (horizontally and vertically) rotating pipe system with a nozzle that allowed the precise aim of the target.