Their eyes did not linger long on the mule for there, stepping boldly out on the slightly swaying bridge, that even seen from above appeared to shudder, was the mysterious, little gray haired man, Malcomb MacQueen.

“Go back! Go back!” Ballard shouted these words. But the wind was against him. The aged man was slightly deaf. Apparently he did not hear for he walked straight on.

The three boys stood aghast, watching. Now he was ten feet from the solid rock he had left, now twenty, now thirty.

“I—I’m going down there,” Bex muttered hoarsely. Next instant like a miniature landslide, he went plunging down the perilous slope.

Cupping his hands, Ballard shouted once again:

“Go back! Mr. MacQueen! Go back!”

This time, his voice, sharpened with an edge of despair, carried far. The man on the bridge paused. He looked up. Ballard heaved a sigh of relief. “Surely now he will turn back,” he told himself.

But apparently he had not been understood for the old man merely waved a hand, then went on, a step, two, three steps,—while the ancient, rusty bridge shuddered and swayed more and more.

Then, when all hope seemed gone, a miracle appeared to have happened. Bex who, mere seconds before, had stood beside the boys, appeared at the end of the bridge beneath them.

“Mr. MacQueen!” he screamed, “go back! The bridge is not safe. Too much weight. It will break. Go back! Go back!”