“Father, I haven’t got the book of notes,” whispered George, thankfully. “I gave them to Timmy. I did manage to get that stone away from the entrance to his little prison — though the men think I didn’t! I gave the book to Timmy and told him to go and hide till I fetched him.”

“Fine work, George!” said her father. “Well — perhaps if you got Timmy now and brought him here — he could deal with these two men before they suspect he is free! He is quite capable of getting them both down on the ground at once.”

“Oh yes! It’s our only chance,” said George. “I’ll go and get him now. I’ll go a little way along the passage and whistle. Father — why didn’t you go and try and rescue Timmy?”

“I didn’t want to leave my book,” said her father. “I dared not take it with me, in case the men came after me and found it. They’ve been looking in all the caves for it. I couldn’t bear to leave it here, and go and look for the dog. I was sure he was all right, when I saw the men taking biscuits out of the bag. Now do go, George, and whistle to Timmy. The men may be back at any moment.”

George took her torch and went into the passage that led to the little cave where Timmy had been. She whistled loudly, and then waited. But no Timmy came. She whistled again, and then went farther along the passage. Still no Timmy.

She called him loudly. “TIMMY! TIMMY! COME HERE!” But Timmy did not come. There was no sound of scampering feet, no joyful bark.

“Oh bother!” thought George. “I hope he hasn’t gone so far away that he can’t hear me. I’ll go a little farther.”

So she made her way along the tunnel, past the cave where Timmy had been, and then on down the tunnel again. Still no Timmy.

George rounded a corner and then saw that the tunnel split into three. Three different passages, all dark, silent and cold. Oh dear! She didn’t in the least know which to take. She took the one on the left.

But that also split into three a little way on! George stopped. “I shall get absolutely lost in this maze of passages under the sea if I go on,” she thought. “I simply daren’t. It’s too frightening. TIMMY! TIMMY!”

Her voice went echoing along the passage and sounded very queer indeed. She retraced her steps and went right back to her father’s cave, feeling miserable.

“Father, there’s no sign of Timmy at all. He must have gone along one of the passages and got lost! Oh dear, this is awful. There are lots of tunnels beyond this cave. It seems as if the whole rocky bed of the sea is mined with tunnels!” George sat down and looked very downhearted.