by the river. The remains of St. Leonard's Hospital chapel and undercroft are on the east side of the gardens, by the Museum Street entrance. The hospital was the largest in England during the Middle Ages, and was run by a community of men and women of the Augustinian order. During the 14th century, the hospital could have contained as many as 240 patients, 18 clergy and 30 choristers. St. Leonard's Hospital was closed during the dissolution of the monasteries, when it was surrendered to Henry VIII by Thomas Magnus. The undercroft and chapel were part of the infirmary built between 1225 and 1250. The interior of the undercroft, accessible from the gardens, has a rib vaulted ceiling and houses a collection of Roman and medieval stonework. In 1999, the hospital and surrounding area in Museum Gardens was one of three sites in York to feature in a live edition of the British Channel 4 television show Time Team. Between the Museum Street entrance to the gardens and the River Ouse is a short stretch of York's city walls, which ends at the medieval Lendal Tower. 19th and 20th century William Hincks was instrumental in establishing the gardens. Henry John Wilkinson reports as follows: "Mr. Hincks was lecturer on botany at the York School of Medicine, and the services he rendered to the Yorkshire Philosophical Society for over ten years deserve our grateful thanks. He devoted his leisure time to convert the " waste land " into a botanical and ornamental* garden, and in this work he was ably assisted by the late sub-curator, Henry Baines. " The Yorkshire Philosophical Society constructed several buildings in the gardens during the 19th and early 20th centuries, including the Yorkshire Museum, one of the first purpose-built museums in Britain. The Yorkshire Museum was designed by architect William Wilkins in a Greek Revival style and was officially opened in February 1830. On 26 September 1831 the inaugural meeting of the British Association for the Advancement of Science was held at the Yorkshire Museum. Three of the museum's permanent collections are housed in the Yorkshire Museum building all of which have English designated collection status, which means they are "pre-eminent collections of national and international importance". The biology collection contains 200,000 specimens, including both fauna and flora, with most of the collection made up of insects. There are two stuffed specimens of the extinct great