Theodore Wood, The Animal World, A Book of Natural History
“ The only explanation we can really give is that the narwhal's tusk is a weapon used in fighting, just like the antlers of the male deer. At any rate, narwhals have several times been seen as they were taking part in a kind of make-believe battle, and striking and clashing their tusks together just as though they were fencing with swords. And when they are fighting in earnest they must be able to use their long spears with terrible effect, for several times a narwhal has charged a ship, and driven its tusk so deeply into her timbers that it was quite unable to withdraw it. ”
