Manual fire engine, c 1680.
© Science Museum / Science & Society Picture Library
This model may have been made by a 17th century fire-engine maker as a demonstration model. Full-size handles out of scale with the model reinforce this theory. The fire engine consists of two vertical pumps in a metal cistern mounted on a sled. The cistern has to be filled with water brought in buckets. When the handles are worked up and down the pumps force water into a large copper vesel , compresing the air within. The air presure ejects the water in a continuous stream once the water rises above the outlet pipe.