听力原文： The British Museum originated in the private collections of Sir Hans Sloane, which he left to the nation on his death in 1753. He was a rich physician who devoted his whole life to collecting curiosities from all parts of the world. These curiosities, together with George the Second's library, were reopened to the public as the British Museum in 1759. Many valuable legacies, especially private libraries and collections of art, have been left to the Museum at different times. An entire reconstruction of the original building of the Museum was begun in 1828, and was finished in 1852. Within the building is a large hall, from which open out passages and stairways to the various departments. The treasures of the British Museum are so numerous that even so large a building could not hold everything, and the scientific and zoological collections have been housed in a separate building in Kensington, known as the Natural History Museum. Within the British Museum itself house the archaeological departments and the library, consisting of more than two million printed volumes with thousands of manuscripts. What is the origin of the British Museum?