She soon came to Olly’s Yard. There it lay below her, with Wooden-Leg Sam pottering about. She went down to speak to him. He didn’t see or hear her coming and jumped violently when she called to him.

He swung round, squinting at her fiercely. “You clear off!” he shouted. “I’ve been told to keep you children outa here, see? Do you want me to lose my job?”

“Who told you to keep us out?” asked George, puzzled as to who could have known they had been in the yard.

“He did, see?” said the old man. He rubbed his eyes, and then peered at George short-sightedly again. “Bruck me glasses,” he said.

“Who’s ‘he’ — the person who told you to keep us out?” said George.

But the old watchman seemed to have one of his sudden queer changes of temper again. He bent down and picked up a large cinder. He was about to fling it at George when Timmy gave a loud and menacing growl. Sam dropped his arm.

“You clear out,” he said. “You don’t want to get a poor old man like me into trouble, do you? You look a nice kind boy, you do. You wouldn’t get Wooden-Leg Sam into trouble, would you?”

George turned to go. She decided to take the path that led to the tunnel and peep inside. But when she got there there was nothing to see. She didn’t feel that she wanted to walk all alone inside that dark mouth, so she took the path that Julian had taken the night before, over the top of the tunnel. But she left it half-way to look at a curious bump that jutted up from the heather just there.

She scraped away at the heather and found something hard beneath. She pulled at it but it would not give. Timmy, thinking she was obligingly digging for rabbits, came to help. He scrambled below the heather — and then he suddenly gave a bark of fright and disappeared!

George screamed: “Timmy! What have you done? Where are you?”

To her enormous relief she heard Timmy’s bark some way down. Where could he be? She called again, and once more Timmy barked.

George tugged at the tufts of heather, and then suddenly she saw what the curious mound was. It was a built-up vent hole for the old tunnel — a place where the smoke came curling out in the days when trains ran there often. It had been barred across with iron, but the bars had rusted and fallen in, and heather had grown thickly over them.

“Oh, Timmy — you must have fallen down the vent,” said George, anxiously. “But not very far down. Wait a bit and I’ll see what I can do. If only the others were here to help!”

But they weren’t, and George had to work all by herself to try and get down to the broken bars. It took her a very long time, but at last she had them exposed, and saw where Timmy had fallen down.