Within days of the Titanic’s sinking, talk began of finding the wreck. Given the limits of technology, however, serious attempts were not undertaken until the second half of the 20th century. In August 1985 Robert Ballard led an American-French expedition from aboard the U.S. Navy research ship Knorr. The quest was partly a means for testing the Argo, a 16-foot (5-metre) submersible sled equipped with a remote-controlled camera that could transmit live images to a monitor. The submersible was sent some 13,000 feet (4,000 metres) to the floor of the Atlantic Ocean, sending video back to the Knorr. On September