the long way to the place. He tore
off his coat, kicked off his canvas shoes, and, reaching the edge of the
water, dived in head first without a word of explanation to the man and
girl beside him.

He dived slantingly, and swam under water for a long way. When he came up
he was a quarter of the distance across the inlet. He shook the water
from his eyes, threw himself breast high out of the sea, and shouted:

"Has she come up? I don't see her!"

Nobody but Mary Cox knew what he meant. Helen and the other girls were
screaming because they had seen Tom fling himself into the sea but they
had not seen Ruth fall in.

Nor did Mary Cox find voice enough to tell them when they ran along
the ledge to try and see what Tom was swimming for. The Fox stood with
glaring eyes, trying to see into the deep pool. But the pool remain
unruffled and Ruth did not rise to the surface.

"Has she come up?" again shouted Tom, rising as high as he could in
the water, and swimming with an overhand stroke.

There seemed nobody to answer him; they did not know what he meant.
The boy shot through the water like a fish. Coming near the rock, he
rose up with a sudden muscular effort, then dived deep. The green water
closed over him and, when Helen and the others reached the spot where
Mary Cox stood, wringing her hands and moaning, Tom had disappeared as
utterly as Ruth herself.

CHAPTER XVI

RUTH'S SECRET

"What has happened?"

"Where's Ruth?"

"Mary Cox! why don't you answer?"

The Fox for once in her career was stunned. She could only shake her head
and wring her hands. Helen was the first of the other girls to suspect
the trouble, and she cried:

"Ruth's overboard! That's the reason Tom has gone in. Oh, oh! why
don't they come up again?"

And almost immediately all the others saw the importance of that
question. Ruth Fielding had been down fully a minute and a half now,
and Tom had not come up once for air.

Nita had set off running around the head of the inlet, and Crab shuffled
along in her wake. The strange girl ran like a goat over the rocks.

Phineas, who had been aboard the motor boat and busy with his famous
culinary operations, now came lumbering up to the spot. He listened to a
chorused explanation of the situation--tragic indeed in its appearance.
Phineas looked up and down the rocky path, and across the inlet, and
seemed to swiftly take a marine "observation." Then he snorted.

"They're all right!" he excl