外装水雷
A early type of torpedo in which the explosive is mounted at the end of a long stick (the spar). Requires the ship using it to get really close to the enemy. Used successfully on a number of occasions during the US Civil War, was made obsolete with the advent of the self-propelled [[torpedo]].

h4.External links

* "Wikipedia":[https://en.wikipedia.org/wiki/Spar_torpedo]
spar torpedo