Dr. Abell, in one of his lectures on phrenology, related a very striking anecdote of a Newfoundland dog at Cork. This dog was of a noble and generous disposition, and when he left his master's house was often assailed by a number of little noisy dogs in the street. He usually passed them with apparent unconcern, as if they were beneath his notice.
One little cur, however, was particularly troublesome, and at length carried his petulance so far as to bite the Newfoundland dog in the back of his foot. This was too much to be patiently endured. He instantly turned round, ran after the offender, and seized him by the skin of his back. In this way he carried him in his mouth to the quay, and holding him some time over the water, at length dropped him into it.
He did not seem, however, to wish to punish the culprit too much, for he waited a little while the poor animal, who was unused to that element, was not only well ducked, but near sinking, when he plunged in himself, and brought the other safe to land.
-- Also from Edward Jesse, Anecdotes of Dogs; pp. 156-7.