9th Experiment.
Torpedo:—19 lbs. of dynamite, enclosed in a cylindrical steel case with arched ends. It was placed 10·5' from No. 3 frame, 9·25' below the surface of the water.
Effect of explosion:—Effect produced apparently equal to that by No. 3 charge of 112 lbs. of gunpowder at 12'; indentation being from 1/2 to 1-1/4 inches in the outer skin opposite the torpedo.