The eighteenth-century professors of physics at Leiden University were very interested in steam power. They devised nice demonstration experiments and models were bought of the great steam engines used in the English coalmines. The most attractive and largest of these was this model of Thomas Newcomen's successful steam pump. On the left is the boiler with the cylinder; the actual steam engine, that is. On the right is the pump, which had to pump up the water. In this model the water was brought up in a bucket, but in reality the right-hand side of the machine went down into the depths of the mine.With its large models the University of Leiden was in the forefront of propaganda for steam in the Netherlands. It was not particularly successful, because steam power was all well and good, but the wind blew for free, Consequently the windmill was a much cheaper option to keep the polders dry.