human
It is wonderful how easily dogs which are always shot over by the same man--he being one who knows his business--will learn to cross and re-quarter their ground, turning to the slightest whistle, and following the least gesture of the hand. I have seen old dogs turn their heads to catch their master's eye, if they thought the whistle too long deferred; and I lately lost an old Irish setter, which had been stone deaf for his last two seasons, but which I found no more difficulty in turning than any other dog, so accurately did he know when to look for the signal.