2nd Experiment.
Countermine:—As before, but moored 27' below the surface.
Submarine mines:—As before, but moored at distances of 70' to 120' from the countermine, and 27' below the surface.
Effect of explosion:—The submarine mine case at 120' distance was dented, but remained water-tight; the copper guard of fuze piece collapsed, and the earth connection of the fuzes was ruptured; the dome of its circuit closer was dented.