It wasn't his nature to bark.

As Bull tore enthusiastically about, Whitey would watch him with a rueful smile, and say, "The only way he could help would be by going home, and of course he can't do that." "In early October a crisp morning found Injun and Whitey leaving camp to begin what for them was a special day's hunting.

They were going for deer.

The deer loved the secluded shores of the lake, and some distance from the camp a run led to a spot where the animals came down to drink.
This morning the camp was down the wind from that spot; so it was ideal.
The boys planned to go in the canoe, and Sitting Bull was securely tied to a tree to await their return.

But Bull looked so longing, so lonely, there was so much entreaty in his eyes, that Whitey allowed his heart to overrule his head.
"He can't raise much of a row in the canoe, and he won't bark," Whitey said rather shamefacedly.