The Italian pronouncement 'things planted should reflect the shape of things built' had ensured that gardens were essentially open-air buildings and the making of them the province of architects. England was committed to a version of the French geometric extension garden but with an emphasis on English grass lawns and gravel walks. Chatsworth's garden is one of the most famous in the United Kingdom. There is a staff of approximately 20 full-time gardeners. This is the Emperor Fountain: in 1843 Tsar Nicholas I of Russia informed the Duke, who was an acquaintance, that he was likely to visit Chatsworth the following year. In anticipation of this Imperial visit the Duke decided to construct the world's highest fountain, and set Paxton to work to build it. An eight-acre (32,000 m²) lake was dug on the moors 350 feet (110 m) above the house to supply the natural water pressure. The work was finished in just six months, continuing at night by the light of flares, and the resulting water jet is on record as reaching a height of 296 feet (90 m). Due to the limited supply of water it usually runs on partial power and is around half that height, but occasionally it is switched to maximum flow.The Tsar never arrived to see his fountain. The water power found a practical use generating Chatsworth's electricity from 1893 to 1936. The house was then connected to the mains, but a new turbine was installed in 1988, and it produces about a third of the electricity the house needs, making this old house a thoroughly modern example of sustainable development. The fountain provides the tallest jet of water in the UK - all the more remarkable for being completely gravity-fed, and more than 150 years old. Chatsworth's gardens are well-known for their waterworks, and they are completely gravity-fed from a number of man-made lakes high on the hillside, 400 feet above the house. These lakes are fed by the myriad of streams that run through the Derbyshire moors.