Then a light broke across the Professor's face. He gave a great gulp of relief.

"My skeleton!" he murmured. "Mr. Quest, I knew it. You are the greatest man alive. Now tell me quickly--I want to know everything, but this first of all.--Where did you find the skeleton? Who was the thief?"

"We found the skeleton, Professor," Quest replied, "within a hundred yards of this house."

The Professor's mouth was wide open. He looked like a bewildered child. It was several seconds before he spoke.

"Within a hundred yards of this house? Then it wasn't stolen by one of my rivals?"

"I should say not," Quest admitted.

"Where? Where exactly did you find it?" the other insisted.

Quest was standing very still, his manner more reserved even than usual, his eyes studying the Professor, weighing every spoken word.

"I found it in a hut," he said, "hidden in a piano box. I found there, also, a creature--a human being, I must call him--in a state of captivity."

"Hidden in a piano box?" the Professor repeated wonderingly. "Why, you mean in Hartoo's sleeping box, then?"

"If Mr. Hartoo is the gentleman who tried to club me, you are right,"

Quest admitted. "Mr. Ashleigh, before we go any further I must ask you for an explanation as to the presence of that person in your grounds!"

The Professor hesitated for a moment. Then he slowly crossed the room, opened the drawer of a small escritoire, and drew out a letter.

"You have heard of Sir William Raysmore, the President of the Royal Society?" he asked.

Quest nodded.

"This letter is from him," the Professor continued. "You had better read it."

The criminologist read it aloud. Lenora looked over his shoulder:--

"To Professor Edgar Ashleigh, New York.

"My dear Professor,

"Your communication gratifies and amazes me. I can say no more.

It fell to your lot to discover the skeleton of the anthropoid, a marvellous thing, in its way, and needing only its corollary to form the greatest discovery since the dark ages. Now you tell me that in the person of Hartoo, the last of the Inyamo Race of South America, you have found that corollary. You have supplied the missing link. You are in a position to give to the world a definite and logical explanation of the evolution of man. Let me give you one word of warning, Professor, before I write you at greater length on this matter. Anthropologists are afflicted more, even, than any other race of scientific men, with jealousy. Guard your secret well, lest the honour of this discovery should be stolen from you.

"WILLIAM RAYSMORE."

[Ill.u.s.tration: QUEST AND LENORA RECEIVE THE MESSAGE FROM LAURA.]

[Ill.u.s.tration: QUEST IS SURPRISED AT FINDING THE STOLEN NECKLACE IN THE BLACK BOX.]

The Professor nodded deliberately as Quest finished the letter.

"Now, perhaps, you can understand," he said, "why it was necessary to keep Hartoo absolutely hidden. In a month's time my papers will be ready. Then I shall electrify the world. I shall write not a new page but a new volume across the history of science. I shall--"

The door was suddenly thrown open. Craig sprang in, no longer the self-contained, perfect man-servant, but with the face of some wild creature. His shout was one almost of agony.

"The hut, Professor! The hut is on fire!" he cried.

His appearance on the threshold was like a flash. They heard his flying feet down the hall, and without a moment's hesitation they all followed.

The Professor led the way down a narrow and concealed path, but when they reached the little clearing in which the hut was situated, they were unable to approach any nearer. The place was a whirlwind of flame. The smell of kerosene was almost overpowering. The wild yell of the leopard rose above the strange, half-human gibbering of the monkeys and the hoa.r.s.e, ba.s.s calling of another voice, at the sound of which Lenora and even Quest shuddered. Then, as they came, breathless, to a standstill, they saw a strange thing. One side of the hut fell in, and almost immediately the leopard with a mighty spring, leapt from the place and ran howling into the undergrowth. The monkeys followed but they came straight for the Professor, wringing their hands. They fawned at his feet as though trying to show him their scorched bodies. Then for a single moment they saw the form of the ape-man as he struggled to follow the others. His strength failed him, however. He fell backwards into the burning chasm.

The Professor bade them farewell, an hour later, on the steps of the house. He seemed suddenly to have aged.

"You have done your best, Mr. Quest," he said, "but Fate has been too strong. Remember this, though. It is quite true that the cunning of Hartoo may have made it possible for him to have stolen the skeleton and to have brought it back to its hiding-place, but it was jealousy--cruel, brutal, foul jealousy which smeared the walls of that hut with kerosene and set a light to it. The work of a lifetime, my dreams of scientific immortality, have vanished in those flames."

He turned slowly away from them and re-entered the house. Quest and Lenora made their way down the avenue and entered the automobile which was waiting for them, almost in silence. The latter glanced towards his companion as they drove off.

"Say, this has been a bit tough for you," he remarked. "I'll have to call somewhere and get you a gla.s.s of wine."

She tried to smile but her strength was almost gone. They drove to a restaurant and sat there for a some little time. Lenora soon recovered her colour. She even had courage to speak of the events of the afternoon when they re-entered the automobile.

"Mr. Quest," she murmured, "who do you suppose burned the hut down?"

"If I don't say Craig, I suppose you will," he remarked. "I wonder whether Laura's had any luck."

They were greeted, as they entered Quest's room, by a familiar little ticking. Quest smiled with pleasure.

"It's the pocket wireless," he declared. "Let me take down the message."

He spelt it out to Lenora, who stood by his side:

"Have joined Servants' Club disguised as your butler. Craig frequent visitor here ten years ago, comes now occasionally.

Thursday evenings most likely time. Shall wait here on chance of seeing him."

"Good girl, that," Quest remarked. "She's a rare sticker, too."

He turned away from the instrument and was crossing the room towards his cigar cabinet. Suddenly he stopped. He looked intently towards the sideboard.

"What is it?" Lenora asked.

He did not answer. She followed the direction of his gaze. Exactly in the same spot as before reposed another but somewhat larger black box, of the same shape and material as the previous one.

"Say, who put that there?" he demanded.

Lenora shook her head.

"I locked the door when we went out," she a.s.sured him.

Quest took the box into his hands and removed the lid. It seemed half full of cotton-wool. On the top were a few lines of writing and beneath them the signature of the parted hands. He read the form out slowly:

"Drop all investigation. The hands that return these jewels command it."