One day (they had grub-staked themselves from the proceeds of the raft and left Dawson for the head- waters of the Tanana) the men and dogs were sitting on the crest of a cliff which fell away, straight down, to naked bed-rock three hundred feet below. John Thornton was sitting near the edge, Buck at his shoulder. A thoughtless whim seized Thornton, and he drew the attention of Hans and Pete to the experiment he had in mind. “Jump, Buck!” he commanded, sweeping his arm out and over the chasm. The next instant he was grappling with Buck on the extreme edge, while Hans and Pete were dragging them back into safety.

“It’s uncanny,” Pete said, after it was over and they had caught their speech.

Thornton shook his head. “No, it is splendid, and it is terrible, too. Do you know, it sometimes makes me afraid.”

“I’m not hankering to be the man that lays hands on you while he’s around,” Pete announced conclusively, nodding his head toward Buck.

“Py Jingo!” was Hans’s contribution. “Not mineself either.”

It was at Circle City, ere the year was out, that Pete’s apprehensions were realized. “Black” Burton, a man evil-tempered and malicious, had been picking a quarrel with a tenderfoot at the bar, when Thornton stepped good-naturedly between. Buck, as was his custom, was lying in a corner, head on paws, watching his master’s every action. Burton struck out, without warning, straight from the shoulder. Thornton was sent spinning, and saved himself from falling only by clutching the rail of the bar.

Those who were looking on heard what was neither bark nor yelp, but a something which is best described as a roar, and they saw Buck’s body rise up in the air as he left the floor for Burton’s throat. The man saved his life by instinctively throwing out his arm, but was hurled backward to the floor with Buck on top of him. Buck loosed his teeth from the flesh of the arm and drove in again for the throat. This time the man succeeded only in partly blocking, and his throat was torn open. Then the crowd was upon Buck, and he was driven off; but while a surgeon checked the bleeding, he prowled up and down, growling furiously, attempting to rush in, and being forced back by an array of hostile clubs. A “miners’ meeting,” called on the spot, decided that the dog had sufficient provocation, and Buck was discharged. But his reputation was made, and from that day his name spread through every camp in Alaska.

Later on, in the fall of the year, he saved John Thornton’s life in quite another fashion. The three partners were lining a long and narrow poling-boat down a bad stretch of rapids on the Forty Mile Creek. Hans and Pete moved along the bank, snubbing with a thin manila rope from tree to tree, while Thornton remained in the boat, helping its descent by means of a pole, and shouting directions to the shore. Buck, on the bank, worried and anxious, kept abreast of the boat, his eyes never off his master.

At a particularly bad spot, where a ledge of barely submerged rocks jutted out into the river, Hans cast off the rope, and, while Thornton poled the boat out into the stream, ran down the bank with the end in his hand to snub the boat when it had cleared the ledge. This it did, and was flying down-stream in a current as swift as a mill-race, when Hans checked it with the rope and checked too suddenly. The boat flirted over and snubbed in to the bank bottom up, while Thornton, flung sheer out of it, was carried down-stream toward the worst part of the rapids, a stretch of wild water in which no swimmer could live.

Buck had sprung in on the instant; and at the end of three hundred yards, amid a mad swirl of water, he overhauled Thornton. When he felt him grasp his tail, Buck headed for the bank, swimming with all his splendid strength. But the progress shoreward was slow; the progress down-stream amazingly rapid. From below came the fatal roaring where the wild current went wilder and was rent in shreds and spray by the rocks which thurst through like the teeth of an enormous comb. The suck of the water as it took the beginning of the last steep pitch was frightful, and Thornton knew that the shore was impossible. He scraped furiously over a rock, bruised across a second, and struck a third with crushing force. He