Captain Lewis, therefore, thought of retreating with a quick walk, as fast as the bear advanced, towards the nearest tree; but, as soon as he turned, the bear rushed open-mouthed, and at full speed, upon him.

Captain Lewis ran about eighty yards, but finding that the animal gained on him fast, it flashed on his mind that, by getting into the water to such a depth that the bear would be obliged to attack him swimming, there was still some chance of his life; he therefore turned short, plunged into the river about waist-deep, and facing about presented the point of his espontoon.

The bear arrived at the water's edge within twenty feet of him; but as soon as he put himself in this posture of defence, the bear seemed frightened, and wheeling about, retreated with as much precipitation as he had pursued.

Very glad to be released from this danger, Captain Lewis returned to the shore, and observed him run with great speed, sometimes looking back as if he expected to be pursued, till he reached the woods.

He could not conceive the cause of the sudden alarm of the bear, but congratulated himself on his escape when he saw his own track torn to pieces by the furious animal, and learned from the whole adventure never to suffer his rifle to be a moment unloaded." Captain Lewis now resumed his progress towards the western, or Sun, River, then more commonly known among the Indians as Medicine River.
In going through the lowlands of this stream, he met an animal which he thought was a wolf, but which was more likely a wolverine, or carcajou.
The journal says:-- "It proved to be some brownish yellow animal, standing near its burrow, which, when he came nigh, crouched, and seemed as if about to spring on him.