English: New River Head garden, engine house and coal stores. In the early 18th C, the New River Company decided to pump water up from the Round Pond to the Upper Pond, now the reservoir in Claremont Square. The pump was originally powered by a windmill and an integral horse gin (for use when there was no wind). But the windmill was not a success, and the horse gin had been built slightly too small to enable efficient working. So a new horse gin building was erected around 1720. It was some 50 years later in 1766-8 that a steam engine house was built. It was extended in 1786 when a Boulton-Watt steam engine was installed. Steam power was replaced by electricity in 1950. The engine house and associated buildings survive relatively unaltered (other than that the engine house has lost its chimney); the buildings were listed in 1972 and have been little used since.