The Natural History Museum has been at South Kensington, London in the romanesque style building of Alfred Waterhouse since 1881. Before that it existed as the Natural History Department of the British Museum, when that institution was established in 1759, with the collections of Sir Hans Sloane, offered to the nation on his death in 1753. The separation of the natural history collections to a new building at South Kensington was forced on the Trustees as a result of the rapid growth of those collections since the Museum's foundation, but especially during the late 18th and early 19th centuries. This growth of collections and libraries has, of course, continued right down to the present time, and has compelled the Trustees to transfer some parts of the Natural History Museum to out-stations, such as, for example, the Zoological Museum, Tring, where the ornithological collections are now housed.