But Benny had found his tongue and his wits.  “There they go, climbing on to the resting-place.  They’ll stay a second there, and—­”

But at that instant he broke off, and dashing into the shack, seized the white tablecloth, scattering the supper dishes far and wide.  With a rush he was at a point of rock which the dying sun flooded with a brilliant red light.  In this radiance the boy stood, swinging about his head the white cloth until it circled five times, then dropped to his feet.  Seizing it again, he held it at arm’s length in his right hand, then dexterously tossed it over his head and caught it in his left.

“Oh, I wonder if they see me!” he cried, shakily, then once more went through the signals.  A faint, far whistle reached his ears.  Then, in a weakness of relief, he dropped down on the rocks, shouting, “They’ll never budge, dad.  They understand.”

But Mr. Ellis was already in the boat, revolver in hand, and three seconds later he and Benny were pulling for all they were worth towards the shivering swimmers, who crouched on the resting-place, unconscious of why they must remain there, or what danger threatened.

Very little was said until Benny and his dad had them safely in the boat, and had rowed them round the rock and pointed silently at the bear and cubs, which still lapped the water at the edge of the beach.  As she caught sight of the boat, the mother growled sullenly, and her red tongue dripped saliva as she started for them until she was breast high in the water.  But strong arms pulled the boat out far beyond danger, and the tragedy that might have been was averted by a boy’s invention and quick wit.  It was very late when the Ellis family had supper that night, but Mrs. Ellis did not mind the broken and scattered dishes when she saw what a rescue Benny had accomplished.  They all talked until they were tired, just as the McKenzie boys talked at their camp.  Later Mr. and Mrs. McKenzie rowed across the lake in the dark, to tell their gratitude to Benny and his father.  But Mr. Ellis would have none of it.  “You just owe it to Benny, here,” he laughed.  “But what he did with that white tablecloth beats me.”

“That’s part of my signal code,” said the boy, a little shyly.  “I invented it; it’s our Scout Society Code, but I don’t mind telling you, after all this, that three circles of any white cloth above one’s head means ‘Danger,’ five circles means ‘Great Danger,’ and a toss from one hand to the other up through the air means ’Don’t move.  Stay where you are.’”

“Well, I never knew that child’s play would save my boys’ lives,” said Mr. McKenzie gratefully.  “I knew these kiddies had some fool ‘code’ they played at, but this beats me, as well as you.”

“It’s no ‘fool’ code, friend Mack,” answered the engineer.  “It’s what an engine whistle or the swing of a lantern is to us trainmen, and I’m glad our boys play at something so sensible.  It’s a mighty good thing once in a while, as we saw to-day—­this ‘Signal Code.’”