Jack had known the fellow at once, had recognised him instantly as the small, dark man who had stood in front of him upon Rushmere Heath and demanded that he should produce his father's letter. An instant conviction had darted into Jack's mind that these things were connected, and that this man knew something of his father's disappearance.

"I've got you this time," cried Jack, and was upon him in a second. But a most astonishing thing happened. The small, slight man offered no resistance to Jack's fierce rush, instead, he seemed to give way before it as a reed gives way before the wind. Then he bent slightly and laid one small, sinewy hand on Jack's knee, and, in some mysterious fashion or another, the lad felt that his hold was torn away, and that he was flying through the air over the little man's head. All in a heap Jack landed on the dusty floor. As he fell, he caught a glimpse of Buck's head thrust through the swinging door as he followed his young leader, and saw the look of surprise on Buck's face.

"Seize him!" roared Jack, and Buck darted forward as the dark stranger shot through another door and vanished into a crowd which swarmed on to the platform from a train which had just drawn up. Jack gathered himself together, and sprang to his feet, and rushed after his companion. He soon found Buck, who was hurrying through the groups, looking about on every hand, and they searched together, but searched in vain; the mysterious stranger had gone to earth safely amid the ample cover provided by the mass of bustling passengers. At last they pulled up and looked at each other.

"No go," said Jack, "he's lost in the crowd. He may be far enough away by now."

Buck's look of wonder and surprise was striking to behold.

"See here, Jack," he said, laying his hand on his companion's arm. "How in thunder do you come to know Saya Chone, and jump on him at sight like a hawk droppin' on a chicken?"

"You know him, Buck?" cried Jack. "You know his name?"

"Know him all right," replied Buck. "But what under the sun is he doing this distance from home? What brings Saya Chone in Brindisi? The last time I set eyes on him he was coming into Mogok with a little bag of rubies to sell to U Saw, the chap they call the Ruby King."

"He comes from Burmah, where you have been?"

"Sure thing," said Buck, nodding his head. "He's a half-caste. Says his father was a British officer, and prides himself on talking Number One English."

"He talked English as easily as we do," said Jack, "but with an odd click of the tongue."

"That's the native strain in him," returned Buck. "But where did you run up against him and hear his English?"

Jack told his story quickly, and Risley listened with a knitted brow of attention.

"Say, there's business at the back o' this," murmured Buck, "but where it fits in beats me at the moment. We don't know enough, Jack, to be sure which way we're moving."

"We do not, Buck, you are quite right," replied the lad, "and we'll make a bee-line for London and see the firm for whom father was working."

"Let's go and see what tar-brush was talking to the interpreter about," suggested Buck, and they went at once and found the man, who had returned to his post on the platform. The interpreter readily told them that the half-caste had offered him a liberal sum in order to learn what Jack was doing, and what route he intended to follow on leaving Brindisi, but the man declared that he had made no answer, had, indeed, been unable to reply to the questions before Jack was on the scene and making his rush.

"Is it worth while to stop here and put the police on the search for this fellow, I wonder?" said Jack, as he and his companion returned to the hotel.

"I doubt it," returned Buck. "There are such numbers of foreigners of all kinds passing through the port that the police can't keep track of them all. Besides, it would take time, and if there's some queer game in the wind, we've lost a good deal now. If you could learn, Jack, how matters stand between the Professor and the firm that sent him out to Burmah, it might give you a line to go on. At present we're snuffin' the wind and pickin' up no scent."

"You're right, Buck, we'll get the baggage together at once."

Again Jack rushed across Italy, France, and the Channel, never pausing for one instant on the way. It was a little before noon on a Thursday morning when he saw London again, and, at the terminus, he parted with Buck.

The latter went with the baggage to Lincoln's Inn to report to Mr. Buxton, while Jack, too anxious to lose another moment, jumped into a cab and drove straight to the offices of Messrs Lane & Baumann in Old Broad Street. He sent his name in, and was shown at once into a large room where Mr. Lane, the senior partner, sat at his desk.

"Ah, Mr. Haydon," said he, "you have, I hope, come to give us some news about your father."

"Unfortunately I have not," replied Jack. "I have been in Brindisi making every inquiry possible, but I have been able to gather no information whatever as to his whereabouts. I have come here in hopes that you may give me some idea of what his arrangements were with you, and from that I might plan a course of action."

"I think my partner had better join us," said Mr. Lane, taking up a speaking-tube. For a few moments nothing was said. The business man went on with the letter he was writing, and Jack looked about him. The office was large and splendidly fitted up. Jack knew nothing of Lane & Baumann, but it was plain on every hand that it was a large and wealthy firm. Mr. Lane himself was an elderly gentleman, irreproachably dressed, and the picture of an important man in the City.

The door opened and the other partner came in. Jack saw that Mr. Baumann was much younger, a fat, heavy German with clean-shaven face and big, round spectacles, through which little, thick-lidded eyes peered.

"Has he brought some news?" asked Baumann quickly. "What does he say?" His accent at once betrayed him, though his English was excellent.

"No," said Mr. Lane quietly, "he has brought no news. He comes to learn of us."

"To learn of us," said Baumann slowly; "and what is it you wish to learn?" he demanded of Jack.

The latter eyed the German keenly. At the first word he detected an enemy. Mr. Lane had been gravely polite and non-committal in his manner. This man showed hostility at once.

"I wish to learn anything that will aid me in discovering the reason for the mysterious disappearance of my father," replied Jack, firmly.

"Mysterious disappearance," repeated the German, with a sneering stress upon the words. "Ach Gott! it is no mystery to me when a man with such a gombanion as that disappears." He was becoming excited, and his German accent began to thicken.

"Companion," repeated Jack, "I do not understand you. My father had no companion except Buck Risley, his man, who has now returned to London with me."

"Had he not, indeed?" said Baumann. "But he had a very close gombanion, one who might easily lead him astray. Himmel, what was it not worth? I think about it night and day."

"Gently, Baumann, gently," said Mr. Lane. "You are mystifying Mr. Haydon, and I shall explain to him what you mean. He clearly does not understand you, and I do not think it is right to keep him in the dark. Mr. Haydon, do you know why your father went to Burmah for us?"

"I understood that he was going to survey some concession you had gained," replied Jack.

"My goncession," cried Baumann. "I went over there and saw the place, and I said to myself, Himmel, here is the for rubies, yes, fine rubies, and I got all rights to dig there."

Mr. Lane quieted his excited partner and turned once more to Jack.

"Exactly," he said; "your father went to survey a concession for us. My partner had been over the ground, and had returned convinced that there was a fine field for ruby-mining. We sent your father out to look carefully over the ground on our behalf, and a short time ago we received some very startling news from him. He cabled to us that in a fissure of the rock, where, as everyone knows, the finest rubies are found, he had made a most marvellous find. He had come across a ruby of priceless quality, and, as his work was done, he intended to return at once, bringing the ruby with him in order to place it himself in our hands."

"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 noble 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.