He relinquished all attempts to swim and centred his efforts in keeping afloat.

If only Norton and the rest would come! He listened.

There was a splashing somewhere nearby, but it was too dark now to see a dozen feet away.

Tom drew all the breath he could find into his lungs and let it out in a weak shout.
"Help!" he gasped.

"Here!" Then there was an answering hail from close by, a mighty churning of the water and a dim form plunged alongside.
"Have you got him ?" cried Norton.