Suddenly Hal thought he heard a call!
Then a man's arm appeared above the water's surface, a few yards away.
"Cramps," yelled Hal to Harry and Bert, while all three hurried to where the man's hand had been seen.
But it did not come up again.
"I'll dive down!" spluttered Hal, who had the reputation of being able to stay a long time under water.
It seemed quite a while to Bert and Harry before Hal came up again, but when he did he was trying to pull with him a big, fat man, who was all but unconscious.
"Can't move," gasped Hal, as the heavy burden was pulling him down.
Bit by bit the man with cramps gained a little strength, and with the boys' help he was towed in to shore.
There was not a life-guard in sight, and Hal had to hurry off to the pier for some restoratives, for the man was very weak. On his way, Hal met a guard who, of course, ran to the spot where Harry and Bert were giving the man artificial respiration.
