Operation Mosaic Captain Hugh Martell would be in charge as commander Task Force 308, with the temporary rank of commodore. Charles Adams from Aldermaston, who had been the deputy technical director to Leonard Tyte for Operation Hurricane and to William Penney on Operation Totem, was appointed the scientific director for Operation Mosaic, with Ieuan Maddock as the scientific superintendent. Group Captain S. W. B. (Paddy) Menaul would command the Air Task Group. Menaul was also a nuclear test veteran, having been an observer on board Vickers Valiant WZ366 when it had made the first operational drop of a British atomic bomb during
Crack in the World atomic device is used and Rampion's fears prove justified, as the crust of the Earth develops an enormous crack that progresses rapidly. Sorenson discovers that there was a huge reservoir of hydrogen underground, which turned the small conventional atomic explosion into a huge thermonuclear one that was millions of times more powerful. Another atomic device, lowered into the magma chamber of an island volcano, is used in the hope of stopping the crack, but it only reverses the crack's direction. Eventually the crack returns to its starting point at the test site, and a huge chunk of the planet outlined