In 1768 Louis de Bougainville found the reef during an exploratory mission, but did not claim the area for the French. On 11 June 1770, the HM Bark Endeavour, captained by explorer James Cook, ran aground on the Great Barrier Reef, sustaining considerable damage. Lightening the ship and re-floating it during an incoming tide eventually saved it. One of the most famous wrecks was the HMS Pandora, which sank on 29 August 1791, killing 35 men. The Queensland Museum has led archaeological digs to the Pandora since 1983. Because the reef had no atolls, it was largely unstudied in the 19th century. During this time, some of the reef's islands were mined for deposits of guano, and lighthouses were built as beacons throughout the system. as in Raine Island, the earliest example. In 1922, the Great Barrier Reef Committee began carrying out much of the early research on the reef.