The great unsinkable liner, of course, was not unsinkable, but she was certainly hard to find. She went down in two-and-a-half miles of water, just on the edge of the Grand Banks where undersea cliffs and plateaus thrust steeply upwards to create the famous fishing grounds; and it took modern technology a long search to locate her. Since then, tiny US Navy sub mersibles equipped with robots have investigated her wreck - or rather wrecks, since the Titanic broke into two huge parts just before she sank. Charles Pellegrino went down on one of these voyages and though his account is written in a hyped-up style which sometimes confuses the narrative as much as it dramatises it, his story is compelling. On the ocean floor lie champagne bottles with the corks and labels intact, coffee cups, suitcases, silver plates, etc., though the wood of the liner's decks and furnishings has turned to pulpy dust and an orange-brown pall covers almost everything. The book also flashes back to the ship's maiden (and last) voyage, with much documentation by survivors, and it seems plain that if Captain Smith had lived, he would have faced severe censure for ignoring warnings and heading at speed into an icefield at night. The photographs, including those taken before the sinking and various underwater views of the wreck, are strangely moving.