Even as he studied the meteoric conditions, Mr. Armitage heard a weird moan. It was the herald of a stiff breeze, possibly half a gale.

Then with a terrific gust the storm burst. It was one of those sudden, fierce tempests that are apt to occur during the summer months—short in duration, but none the less dangerous.

In five minutes the sea was quite tumultuous, although the distance from shore to shore was short of a mile. The Olivette was soon grinding and bumping against the barge in a manner that suggested damage if she remained much longer.

The series of violent concussions brought the Sea Scouts from their bunks. They were prepared to be rocked in the cradle of the deep, but not to be jolted and rattled like peas in a pod. Mr. Murgatroyd alone remained; he was in such a state of mind and body that he hardly cared what happened if only he could set foot on dry land.

"We're dragging, sir," declared Stratton.

It was the unpleasant truth. Either the barge's single anchor had tripped, or else the crew had neglected to pay out sufficient cable. Slowly yet surely the barge, with the Olivette bumping alongside, was drifting down upon the wharves of Gravesend. To make matters worse, the worthy skipper and crew of the barge had not yet returned from the shore.

"We'll have to cut and run for it," declared Mr. Armitage. "Otherwise we stand a good chance of being smashed between the barge and a stone wall. She may ride to her anchor all right without us. Start the engine, Roche, as sharp as you can. Stratton, trim and light the navigation-lamps and set them in position. You others stand by to cast off, but mind you aren't thrown into the ditch."

Fortunately the motor was still warm, and starting up was quickly accomplished. It was, however, a difficult, not to say dangerous, task to cast off from the barge, since it was the Olivette's rope that secured her.

"I'll do it, sir," volunteered the Patrol-leader. "If you went, and anything happened so that you couldn't get back from the barge, where would we be?"

Mr. Armitage saw the force of the argument.