"And now he has mysteriously disappeared," sneered Baumann. His meaning was very plain, and Jack leapt to his feet with pale face and shining eyes.

"Sir!" he cried. "Do you dare to hint that the ruby is the cause of my father's disappearance?"

The German smiled, and Jack's anger grew.

"It is impossible!" he cried. "My father is the soul of uprightness and honour. And do you think he would be tempted by a mere stone, whatever its value? He has handled rubies a hundred and a hundred times."

"Ay," snarled the German, "but not such a ruby as this. What did he say himself? What was in his cablegram? 'The finest ruby by far that I have ever seen or handled!' He says that. He, Haydon, the first living expert on rubies, the man who knows everything of every big specimen in existence. _Himmel, Himmel_, what a stone was that! And what time are we losing! I would set every police of the world on his track. And we do no nothing, nothing!"

"Gently, Baumann, gently, you know very well that I do not agree with you," said Mr. Lane.

Jack turned eagerly to the senior partner. He felt that the whining German was below both his anger and contempt.

"Sir," said Jack earnestly, "if my father had in his charge a stone so immensely precious, I fear he has met with foul play."

"Who knew of it?" said Mr. Lane. "Had he mentioned anything about it to his man?"

"No, he had not," said Jack, and narrated at once what he had heard from Buck Risley.

"Yes," said Mr. Lane, nodding, "it was the possession of the great jewel which made him uneasy."

"Who can say what it was worth?" broke in Baumann fiercely. "A big ruby of perfect colour and without flaw, remember, he said its like did not exist, is of all stones the most precious. Diamonds, poof!

This ruby was worth a score of great diamonds."

"And if my father had with him so wonderful a stone," urged Jack on Mr. Lane, "is it not almost certain that someone has learned of its existence? and again I say that he has met with foul play."

"But who should know of it?" said Mr. Lane. "It is most unlikely that he should mention it to anyone; and you say, moreover, that his own companion knew nothing of it."

"But," cried Jack, and thought this point was a clincher, "he cabled home to you about it, and word of it got abroad, perhaps, from the telegraph office."

Mr. Lane shook his head. "He cabled to us in cipher," he said; "a cipher which he had composed himself and wrote down for us before he started. The paper has been safely locked up in our strong-room, and it was the only copy in the world, for he told us that, for himself, he should carry the cipher in his memory."

This was puzzling and baffling, and Jack was silent. In a moment he put forward another point.

"But we are not sure the ruby has disappeared with my father," he said; "it may be packed away in his baggage."

Mr. Lane shook his head once more. "No," he said, "that is very unlikely. Your father would be certain to carry a thing so small and so valuable on his person. He would never part with it night or day."

Again there was a short interval in which nothing was said. Into this silence suddenly broke the grumbling roar of Baumann's great voice.

The German had been brooding over the disappearance of the great stone until he was beside himself.

"_Ach Gott_," he cried furiously to Mr. Lane. "You are foolish. You still believe in the man and trust him. Me, I do not, I tell you plainly he is a thief. He is to-day perhaps in Amsterdam, cutting that n.o.ble and splendid stone into many smaller ones, and each of them still a fortune. Yes, he is a thief!"

"You liar!" roared Jack. "My father is not a thief. How dare you take such words on your dirty lips in respect of such a man!"

He had bounded to his feet and clenched his fists. Mr. Lane sprang between them.

"Now, Mr. Haydon," said the elder man, "you must keep the peace.

Baumann is speaking very wildly. I do not agree with him. I know your father too well."

Respect for Mr. Lane held Jack back, and nothing else. He would dearly have liked to plant his fist on the German's foaming mouth, but he commanded himself with an immense effort, and tried to speak calmly.

"The man is mad to say such things," said Jack with trembling lips.

"Why, the whole facts of the case are against any such monstrous idea.

If my father had wished to steal the stone, would he have cabled to you full particulars and started home? What would have been easier than to pocket it at once, and say nothing?"

"He was not a thief at first," vociferated the German. "He was honest when he cabled. But the jewel, the great, big, beautiful jewel itself corrupted him. He looked at it, and looked at it, till the love of it filled his heart and he could not part with it. _Himmel_, I have felt it all. I know what happened as well as if I had been at his side all the voyage."

"Look here, you foul slanderer," cried Jack. "I'll prove you a liar out and out. Listen to me. I'll find my father if he still remains in existence, and I'll prove that you wrong him by your unjust suspicions." The lad turned to Mr. Lane with flushed face and shining eyes. "I thank you, sir," he said, "for the trust you still retain in my father. I will do my very utmost to prove to you that it was well placed. I cannot promise you anything save that I will do all that lies in my power to trace your great ruby and discover my father's fate at the same time."

Jack could say no more. He held out his hand and Mr. Lane shook it, and the tall English lad strode from the office.

CHAPTER IV.

BUCK SEES LIGHT.

Jack walked rapidly through the city, and, free from the presence of Baumann and his vile insinuations, began to cool rapidly and survey the situation with a steadier eye.

"This needs talking over," he said to himself. "Here's a big new development." He hailed a cab and was driven to Lincoln's Inn. He found Mr. Buxton's sitting-room littered with the baggage they had brought home, and Mr. Buxton himself in close confab with Buck Risley.

"Hullo, Jack," said the elder man, rising to shake hands with him; "how have you been getting on with Lane and Baumann? You look excited."

"Rather, Mr. Buxton," said Jack. "I have been learning a great deal."

He struck into his story at once, and the two men listened with great interest.

"He had an immense ruby of incalculable value in his possession," said Mr. Buxton slowly, when Jack had finished. "I say, this changes the whole situation. I'm afraid, Jack, something very serious has happened to your father."

"Then that's what was on the Professor's mind," cried Buck. "I knew very well there was something. It was big enough to make even him feel uneasy."

"It's an odd thing he didn't mention it to you, Risley," said Mr.

Buxton. "I've always understood that you were privy to all his business movements."

"That's all right, Mr. Buxton," said Risley cheerfully. "You've got that quite straight. In a general way the Professor hid nothing from me. But this time he did hide it about the big stone, and I'm goin' to show you how right, just as usual, the Professor was. You must remember," went on Buck, "that when he picked me up at Mogok on the way home, he found only a dim and distant shadder o' the party now talkin' to you. I'd been on my back for weeks with fever, and was as weak and nervous as a kitten. I've picked up wonderful on the voyage home. Well, if he'd told me o' such a thing as he'd certainly got at that moment in his belt, it would ha' rattled me to pieces. I should have been certain to give the show away in my anxiety for fear anybody should get to know about it, and do him a mischief. So he said nothing at all. But it puts everything in a new light, everything."

"Buck!" cried Jack. "What about that fellow who stopped me on Rushmere Heath and then turned up in Brindisi? Can he have something to do with it?"

"Now you're talking, Jack," said Risley, nodding at the young man.

"'Twas all runnin' through my mind. It all hangs together, as straight as a gun."

Buck knitted his brows in deep thought, and stared into the fire. Mr.

Buxton was about to speak, but Buck held up his hand for silence, and the quiet remained unbroken till the American slapped his knee with a crack like a pistol-shot, looked round on them, and nodded briskly.

"I've worked it out," said Buck. "The Professor's been kidnapped, and I'll lay all I'm worth I can spot the parties who have boned him."

"Kidnapped!" The cry burst in irrepressible surprise and excitement from the other two.