Torpedo ram

The earliest self-propelled torpedoes were obviously very powerful weapons, but were very short-ranged and incapable of reaching speeds greater than 10 knots, making them useless against anything but stationary targets.

The torpedo ram's low profile and high speed were to make discovery and interception harder,[5] as was the commonly stated intent for their attacks to take place at night.

Neither saw a great deal of active service and they were mostly used for torpedo trials, although Polyphemus did demonstrate the potential damage she could inflict when she was used to demolish a harbor defense boom via ramming.

[3] While never popular with the naval services that created them, the torpedo ram can be said to have caught public attention in a manner which far exceeded its utility as a concept for a fighting ship.

The heroic HMS Thunder Child in H. G. Wells' science fiction novel The War of the Worlds is a torpedo ram; she destroys two Martian Tripods before being sunk.