Senestro alone remained untouched. He was about to open the white door; for a second he posed, defiant and handsome. Then the great Bar ducked swiftly and almost with the same motion dodged into the building. Chick and Pat were right after him.

Inside was darkness. Chick ran head on against the side wall; turning, he bumped into another. The sudden transition from brilliance to blackness was overwhelming. He stopped and felt about carefully--momentarily blind. What if the Senestro found him now?

He called MacPherson's name. There was no reply. He tried to feel his way along, finding the wall irregular, jagged, sharp cornered. But the way must lead somewhere. He reached a turn in the passage; it was still too dark for him to see anything. He proceeded more cautiously, wondering at those craggy walls. And then--

Chick slapped his hands to his eyes. It was as if he had been shot into the core of the sun--the obsidian darkness flashed into light--a light beyond all enduring. Chick staggered, and cried in pain. And yet, reason told him just what it was, just what had happened. It was the carbon; he was in the heart of the diamond; the Senestro had led him on and on, and then--had flashed some intense light upon the vast jewel. Watson knew the terrible helplessness of the blind. His end had come!

And so it seemed. Next instant someone came up to him--someone he could hear if he could not see. It was the Senestro.

"Hail, Sir Phantom! Pardon my abrupt manner of welcome. I suppose you have come for the Jarados?" And he laughed, a laugh full of mockery and triumph. "Perhaps you think I intend to kill you?"

Watson said no word. He had been outwitted. He awaited the end. But the Senestro saw fit to say, with an irony that told how sure he was:

"However, I am opposed to killing in cold blood. Open your eyes, Sir Phantom! I will give you time--a fair chance. What do you say--shall we match weapon against weapon?"

Watson slowly opened his eyes. The blinding light had dimmed to a soft glow. They were in a sort of gallery whose length was uncertain; between him and the outlet, about ten feet away, stood the confident, ever-smiling Bar.

"You or I," said he, jauntily. "Are you ready to try it? I have given you a fair chance!"

He raised his dagger-like weapon, as though aiming it. At the same instant Chick pulled the trigger from the hip, snap aim.

The gun was empty.

Another second, and Watson would have been like those spots of colour on the ground outside. He breathed a prayer to his Maker. The Senestro's weapon was in line with his throat.

But it was not to be. There came a flash and a stunning report; the deherer clattered against the wall, and the Senestro clutched a stinging hand. He was staring in surprise at something behind Chick--something that made him turn and dart out of sight.

Chick wheeled.

Right behind him stood the familiar form of the Jan Lucar; and a few feet beyond, a figure from which came a clear, cool, nonchalant voice;

"I would have killed that fellow, Chick, but he's too damned handsome.

I'm going to save him for a specimen."

Watson peered closer. He gave a gasp, half of amazement, half of delight. For the words were in English, and the voice--

It was Harry Wendel.

XLIV

DR. HOLCOMB'S STORY

If there was the least doubt in Chick's mind that this was really Harry, it was dispelled by the sight of the person who the next moment stepped up to his side. It was none other than the Nervina.

"Harry Wendel!" gasped Watson. It was too good to be true!

"Surest thing you know, Chick. It's me, alive and kicking!" as they grabbed one another.

"How did you get here?"

"Search me! Ask the lady; I'm just a creature of circumstance. I merely act; she does all the thinking."

The Nervina smiled and nodded. Her eyes were just as wonderful as Chick remembered them, full of elusiveness, of the moonbeam's light, of witchery past understanding.

"Yes," she affirmed. "You see, Mr. Watson, it is the will of the Prophet. Harry is of the Chosen. We have come for the great Dr.

Holcomb--for the Jarados!"

And she led the way. Watson followed in silent wonder; behind him came the Geos and the rest, quiet and reverent. The soft glow still held, so that they seemed to be walking through the walls of cold fire. At the end of the passage they came to a door.

The Nervina touched three unmarked spots on the walls. The door opened.

The queen stood aside, and motioned for Chick and Harry to enter.

It was a long room, pear-shaped, and fitted up like the most elaborate sort of laboratory. And at the far end, seated in the midst of a strange array of crystals, retorts and unfamiliar apparatus, was a man whom the two instantly recognised.

It was the missing professor, looking just as they remembered him from the days when they sat in his class in Berkeley. There was the same trim figure, the same healthy cheeks, pleasant eyes and close-cropped white beard. Always there had been something imperturbable about the doctor--he had that poise and equanimity which is ever the balance of sound judgment. Neither Chick nor Harry expected any rush of emotion, and they were not disappointed.

Holcomb rose to his feet, revealing on the table before him a queer, dancing light which he had been studying. He touched something; the light vanished, and simultaneously there came an unnameable change in the appearance of certain of those puzzling crystals. The doctor stepped forward, hand extended, smiling; surely he did not look or act like a prisoner.

"Well, well," spoke he; "at last! Chick Watson and Harry Wendel! You're very welcome. Was it a long journey?"

His eyes twinkled in the old way. He didn't wait for their replies. He went on:

"Have we solved the Blind Spot? It seems that my pupils never desert me.

Let me ask: have you solved the Blind Spot?"

"We've solved nothing, professor. What we have come for is, first, yourself; and second, for the secrets you have found. It is for us to ask--what is the Blind Spot?"

The professor shook his head.

"You were always a poor guesser, Mr. Wendel. Perhaps Chick, now--"

"Put me down as unprepared," answered Chick. "I'm like Harry--I want to know!"

"Perhaps there are a lot of us in the same fix," laughed Holcomb. "We, who know more than any men who ever lived, want to know still more! It may be, after all, that we know very little; even though we have solved the problem." His eyes twinkled again, aggravatingly.

"Tell us, then!" from Harry, on impulse as always. "What is the Blind Spot?"

But Holcomb shook his head. "Not just now, Harry; we have company."

The Geos and the Jan had entered. "Besides, I am not quite ready. There remain several tangles to be unravelled."

As he shook hands with the Geos, he spoke in the Thomahlian tongue. "You are more than welcome."

The Rhamda bent low in reverence and awe. His voice was hushed. He spoke:

"Art thou the Jarados, my lord?"