1st Experiment.
Torpedo:—617 lbs. of dynamite. It was 62' horizontally from the keel, 53' actual distance from the side, and opposite amidships, 40·5' below the surface of the water, and 20' from the ground.
Pontoon:—Draught of water 19', and moored in 62' of water.
Effect of explosion:—The pontoon moved away bodily a distance of 13 feet; a few rivets in the outer bottom were started, and the outer skin was slightly indented between the frames; the maximum indentation being 1·5". No other damage was sustained by the hull. Several of the screws securing the flanges of the Kingston valves were slightly loosened.