thesis for his PhD, which he obtained in 1954, and also for a book, published the following year. He believed the work to be by Geoffrey Chaucer, who had written A Treatise on the Astrolabe, but it is now attributed to a St Albans monk called John Westwyk. Price received a Nuffield Foundation award for research in the History of science, which enabled him to work on scientific instruments during 1955–1956. He first prepared a catalogue of the instrument collection of the British Museum, and then a catalogue of all the ancient astrolabes that he was able to locate. While working on his Ph.D. in Cambridge, Price met Joseph Needham, the historian of Chinese science. As a result of his work on the Equatorium Price was invited to participate in a project on medieval Chinese astronomical clocks. This led to the book Heavenly Clockwork by Needham, Wang Ling and Price, which was published in 1960. Another interest in ancient technology concerned the Antikythera mechanism. This machine had been retrieved from a wreck off the island of Antikythera in 1900, and its function had remained unknown. Price started working on this in the 1950s, and continued on and off for twenty years using various techniques including gamma radiography. He published two papers on the mechanism, in 1959 and 1974, showing that it was a planetary computer, dating from about 80 BCE. Also, with Joseph Noble, he studied the machinery of the Tower of the Winds in Athens, and showed it to be water-driven clockwork, showing times and seasons. Around 1950, Price adopted his mother's Sephardic name, "de Solla", as a middle name. He was a "British Atheist ... from a rather well-known Sephardic Jewish family", and although his Danish wife, Ellen, had been christened as a Lutheran, he did not, according to their son Mark, regard their marriage as "mixed", because they were both atheists. After obtaining his second doctorate, Price found advancement difficult in England. One colleague alleged that Price, who came from a lower-class background, was "not socially house-trained," and he suspected that he was turned down for university positions for personal reasons. Price decided to move to the United States. In 1957 he became a consultant to the Smithsonian Institution, and then a fellow at the Institute for Advanced Study in Princeton, New Jersey. At Princeton he studied ancient astronomy with Otto Neugebauer. In 1959 he joined the