“How are we to get Mike back?” asked Nora, much happier now that Dimmy knew everything. “And Paul too - he must be rescued before Friday.”

Dimmy thought for a long time. Then she said something that set the children’s hearts beating with excitement.

“My grandfather once told me that there was a secret way between Peep-Hole tower and the tower of the Old House,” she said. “It was often used by the old-time smugglers when they wanted to get unseen from one house to the other. If we could find it, we could reach the tower of the Old House easily, and fetch back the two boys without anyone knowing.”

“Oh, Dimmy!” cried the three children, their eyes shining brightly. “We must find it! We must, we must!”

“Well, we will hunt for it to-morrow,” said Dimmy. “And I think we must get George to help us, because it will mean using a good deal of strength to find a passage that has been unused and hidden for years. As far as I remember, my grandfather said that a great stone had to be swivelled round in the wall of our tower - and certainly none of us could do that. George is very strong, and he can keep a secret too.”

After talking for a little while longer the children were sent off to bed. Before they got into bed they were very much cheered by seeing Mike at the lighted window of the Old House tower, waving to them in the moonlight. He seemed quite cheerful, and Nora and Peggy were very glad to see him.

“Good old Mike.” said Jack, getting into bed. “I hope he won’t be too miserable.”

“So do I,” said Nora. “And, oh, I do hope we find the hidden way between our tower and the other tower. Won’t George be surprised when he hears all we’ve got to tell him! Oh, to-morrow, do come quickly!”

The next morning when Jack rushed to the window to look at the tower of the Old House he found that Mr. Diaz had kept his word - the window was now boarded up! No messages could be given to the prisoners, and they could send no messages back.

Jack didn’t like it. He had hoped that perhaps Mr. Diaz might have forgotten to block up the window. It made everything seem very serious, when he looked at that blind window with the boards across it.

The children went down to breakfast looking solemn. Nora gave a little sob when she looked at Mike’s empty chair at the table. But Dimmy seemed very cheerful and patted her on the back.

“Don’t worry,” she said. “Now that you’ve told me, I’ll do my best to help - and we’ll rescue both boys, never fear!”

Nobody seemed to want much breakfast, although it was poached eggs, which they all loved. Nora was anxious to do something for Mike and Paul as soon as possible, and she wouldn’t even let Dimmy wash up after breakfast.

“Please do let us see if we can discover the secret door out of our tower,” she begged. “Leave the cups and things, Dimmy dear - we can do those afterwards.”

So Dimmy left them, and the three children trooped up the winding stone staircase with her. They went to Jack’s room and looked round the grey stone walls.

It seemed impossible to find any secret door in those great walls. They knocked on them, they pressed on them, they stood on chairs and pushed against the higher part of the walls, but nothing moved, nothing swung round to show a hidden passage in the thick stone walls.

At eleven o’clock they stopped their hunting, quite tired out. Dimmy looked at Nora’s pale face, and was sorry for her.

“I’m going to make some cocoa for us all, and get some ginger cake,” she said. “We need a rest.”

She ran downstairs. Peggy went with her to help. Nora sat on Jack’s bed and looked gloomy.

“Cheer up, Nora,” said Jack.

“I’m quite, quite sure there’s no hidden door in this room,” said Nora, with a deep sigh.

“I feel as if there isn’t too,” said Jack anxiously. “Wouldn’t it be dreadful if it was only a tale, and not true at all!”

“Don’t, Jack,” said Nora. “You make me feel worse.”

Jack sat and thought for a few minutes. “I wonder if by any chance Dimmy has any old maps of Spiggy Holes in that big bookcase of hers downstairs,” he said. “If she had, one of them might show where the hidden door is.”

Dimmy came into the room at that minute, carrying a big jug of milky cocoa. Peggy followed with a dish of brown gingerbread. Everyone felt quite cheered by the look of it.

“Dimmy, I suppose you’ve no old books about Spiggy Holes, or old maps, have you?” asked Jack, munching his gingerbread.

Dimmy looked surprised. “Why didn’t I think of that before?” she said. “Of course! There are two or three old books about this place, belonging to my great-grand-father. I believe they are very valuable. They are locked up in the big bookcase downstairs.”

Jack almost choked over his cake in his delight. “Let’s get them!” he said, jumping up.

“Finish your cake and cocoa.” said Dimmy. “Then we’ll go downstairs and look for them.”

How the three children swallowed down their cocoa and gingerbread, in their eagerness to rush downstairs to find the old books! It wasn’t more than a minute or two before they were all in Dimmy’s rather dark little drawing-room, watching her whilst she unlocked the big old-fashioned bookcase there.

She moved aside some of the books on the top row, and behind them were some very old books, carefully covered in thick brown paper.

“There they are,” said Dimmy. “This one is called Spiggy Holes - a record of smuggling days. And this one is called Tales of Smugglers, and Spiggy Holes is mentioned several times. This one is only an old cookery book - and this is a diary kept by my grandfather.”

The children pounced eagerly on the first two books. The girls turned over the pages of Spiggy Holes, and Jack looked hurriedly through Tales of Smugglers.

“Look! Look! Here’s a map of the secret passage we know!” cried Peggy suddenly. All the others crowded round her and peeped at the book she was holding. She laid it flat on the table. She pointed to a page on which was drawn a small map, showing Peep-Hole and the Old House and the shore. From the shore-cave to the Old House the secret passage was shown winding its way through the cliff underground to the cellars of the Old House.

“But there’s no way shown from Peep-Hole to the Old House,” said Jack in disappointment.

He was right. There was no hidden path between the two houses on the map. Eagerly Nora turned the pages to see if another map was shown, but there was none.

The two books were a great disappointment. Peggy, who was a good reader, hurriedly read through both of them to see if she could perhaps find anything written about the way between the two towers - but not a word was said.

“It must have been just a tale,” said Nora in disappointment, closing the books.

“I feel sure it wasn’t,” said Dimmy, puzzled. “I remember so well how my grandfather told me about the secret. I wonder if he says anything about it in his old diary. He kept it when he was a boy, and it wasn’t found until a year or two ago. The ink has faded, and it was so difficult to read that I didn’t try more than a few pages. It was all about his days as a boy.”

“Dimmy, let me have it,” said Jack. “I will go away by myself and try to make it all out. It will take me a little time, but I’ll use my magnifying-glass to help me to read your grandfather’s tiny writing.”

Dimmy gave the little paper-covered diary to Jack. He slipped off upstairs with it. The two girls looked at Dimmy.

“What shall we do?” asked Nora. “I don’t feel like bathing or digging without Mike here.”

“Then you can just come and help me to wash up those breakfast things and make the beds and dust and get dinner ready!” said Dimmy briskly. “It will do you good to think of something else for a while.”

“It won’t,” said Peggy dismally. But Dimmy was right. Both girls felt much better about things when they set to work to wash up and to dust.