Tried out in waters at Oakland, Calif, a cruiser floating on a pair of pon-toons is said to be virtually unsinkable. Each pontoon is divided into watertight compartments, and it is claimed that the boat will remain afloat even if half of the compartments become flooded. The inventors say that the pontoon cruiser, which is capable of thirty miles an hour, could serve as a submarine chaser in wartime. Her broad decks, in peacetime, are used by fishermen.