Bill didn't answer. Very much disturbed in his mind, he walked restlessly about the room, frowning to himself, stopping now and then at the newly discovered door and looking at it as if he were trying to learn what lay behind it. Which side was he on, if it came to choosing sides-Mark's or the Law's?

"You know, you can't just say, 'Oh er hallo!' to him," said Antony, breaking rather appropriately into his thoughts.

Bill looked up at him with a start.

"Nor," went on Antony, "can you say, 'This is my friend Mr. Gillingham, who is staying with you. We were just going to have a game of bowls.'"

"Yes, it's dashed difficult. I don't know what to say. I've been rather forgetting about Mark." He wandered over to the window and looked out on to the lawns. There was a gardener clipping the gra.s.s edges. No reason why the lawn should be untidy just because the master of the house had disappeared. It was going to be a hot day again. Dash it, of course he had forgotten Mark. How could he think of him as an escaped murderer, a fugitive from justice, when everything was going on just as it did yesterday, and the sun was shining just as it did when they all drove off to their golf, only twenty-four hours ago? How could he help feeling that this was not real tragedy, but merely a jolly kind of detective game that he and Antony were playing?

He turned back to his friend.

"All the same," he said, "you wanted to find the pa.s.sage, and now you've found it. Aren't you going into it at all?"

Antony took his arm.

"Let's go outside again," he said. "We can't go into it now, anyhow. It's too risky, with Cayley about. Bill, I feel like you-just a little bit frightened. But what I'm frightened of I don't quite know. Anyway, you want to go on with it, don't you?"

"Yes," said Bill firmly. "We must."

"Then we'll explore the pa.s.sage this afternoon, if we get the chance. And if we don't get the chance, then we'll try it to-night."

They walked across the hall and out into the sunlight again.

"Do you really think we might find Mark hiding there?" asked Bill.

"It's possible," said Antony. "Either Mark or-" He pulled himself up quickly. "No," he murmured to himself, "I won't let myself think that--not yet, anyway. It's too horrible."

CHAPTER XII. A Shadow on the Wall

In the twenty hours or so at his disposal Inspector Birch had been busy. He had telegraphed to London a complete description of Mark in the brown flannel suit which he had last been seen wearing; he had made inquiries at Stanton as to whether anybody answering to this description had been seen leaving by the 4.20; and though the evidence which had been volunteered to him had been inconclusive, it made it possible that Mark had indeed caught that train, and had arrived in London before the police at the other end had been ready to receive him. But the fact that it was market-day at Stanton, and that the little town would be more full than usual of visitors, made it less likely that either the departure of Mark by the 4.20, or the arrival of Robert by the 2.10 earlier in the afternoon, would have been particularly noticed. As Antony had said to Cayley, there would always be somebody ready to hand the police a circ.u.mstantial story of the movements of any man in whom the police were interested.

That Robert had come by the 2.10 seemed fairly certain. To find out more about him in time for the inquest would be difficult. All that was known about him in the village where he and Mark had lived as boys bore out the evidence of Cayley. He was an unsatisfactory son, and he had been hurried off to Australia; nor had he been seen since in the village. Whether there were any more substantial grounds of quarrel between the two brothers than that the younger one was at home and well-to-do, while the elder was poor and an exile, was not known, nor, as far as the inspector could see, was it likely to be known until Mark was captured.

The discovery of Mark was all that mattered immediately. Dragging the pond might not help towards this, but it would certainly give the impression in court to-morrow that Inspector Birch was handling the case with zeal. And if only the revolver with which the deed was done was brought to the surface, his trouble would be well repaid. "Inspector Birch produces the weapon" would make an excellent headline in the local paper.

He was feeling well-satisfied with himself, therefore, as he walked to the pond, where his men were waiting for him, and quite in the mood for a little pleasant talk with Mr. Gillingham and his friend, Mr. Beverley. He gave them a cheerful "Good afternoon," and added with a smile, "Coming to help us?"

"You don't really want us," said Antony, smiling back at him.

"You can come if you like."

Antony gave a little shudder.

"You can tell me afterwards what you find," he said. "By the way," he added, "I hope the landlord at 'the George' gave me a good character?"

The Inspector looked at him quickly.

"Now how on earth do you know anything about that?"

Antony bowed to him gravely.

"Because I guessed that you were a very efficient member of the Force."

The inspector laughed.

"Well, you came out all right, Mr. Gillingham. You got a clean bill. But I had to make certain about you.

"Of course you did. Well, I wish you luck. But I don't think you'll find much at the pond. It's rather out of the way, isn't it, for anybody running away?"

"That's just what I told Mr. Cayley, when he called my attention to the pond. However, we shan't do any harm by looking. It's the unexpected that's the most likely in this sort of case."

"You're quite right, Inspector. Well, we mustn't keep you. Good afternoon," and Antony smiled pleasantly at him.

"Good afternoon, sir."

"Good afternoon," said Bill.

Antony stood looking after the Inspector as he strode off, silent for so long that Bill shook him by the arm at last, and asked him rather crossly what was the matter.

Antony shook his head slowly from side to side.

"I don't know; really I don't know. It's too devilish what I keep thinking. He can't be as cold-blooded as that."

"Who?"

Without answering, Antony led the way back to the garden-seat on which they had been sitting. He sat there with his head in his hands.

"Oh, I hope they find something," he murmured. "Oh, I hope they do."

"In the pond?"

"Yes."

"But what?"

"Anything, Bill; anything."

Bill was annoyed. "I say, Tony, this won't do. You really mustn't be so d.a.m.n mysterious. What's happened to you suddenly?"

Antony looked up at him in surprise.

"Didn't you hear what he said?"

"What, particularly?"