The behavior of the gas bubble generated by explosive charges fired below the ocean's surface has been studied by means of a scale model. The motion of the bubble was recorded using a high-speed camera. A small pressure detector was used to record the pressure variation near the bubble. The behavior of the bubble generated by the equivalent of a 15-lb charge was studied with the bubble subjected to the following boundary conditions: a single charge at various depths below the liquid surface, two charges on a vertical axis at various separations and various depths, two charges on a horizontal axis at various separations, a single charge at various separations below a solid plate, and a single charge at various separations to the side of the solid cylinder. Of these methods, the only one which appeared promising was the location of two charges on a vertical axis with both charges within 20 ft of the surface.