This paper was an account of a plan proposed and tried many years ago for poisoning whales, by introducing hydrocyanic acid into their bodies when struck with the harpoon.

In 1831, the author was consulted on the subject by the late Messrs G. and W. Young of Leith, at that time concerned in the northern whale-fishery. It appeared to the author that the idea was feasible; that it was sufficient to paralyse the animal, so that the boats could speedily come up with it; and that a quantity of concentrated hydrocyanic acid, adequate to produce that effect at least, could be introduced by means of two glass tubes, one on each side of the shank of the harpoon, where they would be protected by the barbs of the blade.