Sir William Gouldesbrough stood in the large laboratory. The great room was perfectly dark, save only for a huge circle of bright light upon one of the walls, like the circle thrown upon a screen by a magic-lantern.

A succession of dim and formless figures moved and slid over the illuminated space in fantastic silence. Now and then the face of part of the dress of one of the figures would suddenly glow out into colour and absolute distinctness. Then it would fade away into mist.

There was a "click," and the circle of light vanished, another, and the vast laboratory glowed out into being as Sir William turned on a hundred electric bulbs.

Mr. Guest was sitting upon a long, low table swinging his legs. His great pink face was blotched and stained by excess, and his hand shook like an aspen leaf.

He jerked his head towards the opposite wall upon which the huge screen was stretched—an enormous expanse of white material stretched upon rollers of hollow steel.

"Rathbone's getting about done," he said. "I give him another month before his brain goes or he pegs out altogether. Look at those results just now! All foggy and uncertain. He's losing the power of concentrating his thoughts. Continuous thinking is getting beyond him."

Sir William was sitting in an arm-chair. By the side of it was a circular table with a vulcanite top, covered with switch-handles and controlling mechanism. His long thin finger played with a little brass button, and his face was set in lines of deep and gloomy thought. His eyes were fixed and brooding, and sombreness seemed to surround him like an atmosphere. He showed no signs of having heard his assistant for a moment or two. Then he turned his face suddenly towards him.

"My friend," he said, "you yourself will not last another month if you go on as you are going. That is quite certain. You ought to know it as well as I do. Another attack of delirium and nothing can save you."

Mr. Guest smiled horribly. "Very possibly, William," he said, "I have thought that it may be so myself. But why should I care? I'm not like you. I have no human interests. Nothing matters to me except my work."

"And if you die in delirium tremens you won't be able to go on with your work."

"My dear William, there is nothing left for me to do. In this new discovery of ours, yours has been the master-mind. I quite admit that. But you could not have done without me. I know, as you know, that there is no one else in Europe except myself who could have helped you to bring the toil of years to such a glorious conclusion. Well, there is the end of it. I am nearly fifty years old. There is no time to start again, to begin on something new. Life will not be long enough. I have used up all my powers in the long-continued thought-spectrum experiments. I have no more energy for new things. I rest upon my laurels, content that I have done what I have, and content from the purely scientific point of view. I've fulfilled my destiny. My mind is not like the minds of other men I meet. It is not quite human. It's a purely scientific mind, a piece of experimental apparatus which has now done its work."

He laughed, a laugh which was so mirthless and cold that even Gouldesbrough shuddered at the soulless, melancholy sound. Then he got down from the table and shambled over the floor of the laboratory towards a cupboard. He took a bottle of whisky from a shelf, half filled a tumbler with the spirit, and lifted it towards his chief in bitter mockery.

"Here's luck, William," he said, "luck to the great man, the pet of Europe, the saviour of the race! You see I have been reading Mr. Donald Megbie's articles in the papers." He drank the whisky and poured some more into the glass. "Yet, William, most fortunate of living men! you seem unhappy. 'The Tetrarch has a sombre air,' as the play says. What a pity it is that you are not like me, without any human affections to trouble me! I don't want to pry into your private affairs—I never did, did I?—but I presume something has gone wrong with your matrimonial affairs again? I'm right, am I not? Can't Miss Marjorie make up her mind? Tell me if you like. I can't give you any sympathy, but I can give you advice."

Gouldesbrough flushed and moved impatiently in his chair. Then he began to speak.

"If what you say is true, Guest, then you must be a happy man. Your life is complete, you have got what you wanted, you have done what you wanted to do. And if you choose to kill yourself with amyl alcohol, I suppose that's your affair. What you say is quite right. I am terribly worried and alarmed about the success of my great desire, the one wish remaining to me. I don't expect or want sympathy from you, but your advice is worth having, and you shall give it to me if you will."

Wilson Guest nodded. "Tell me what is worrying you," he said.

"You know that I have had great hopes of obtaining Miss Poole's consent to our re-engagement. Everything has been going on well. Miss Poole believes—or did believe—that the man Rathbone is dead. I used your suggestion and hinted at a vulgar intrigue. At Brighton, when Charliewood shot himself, I was constantly with Miss Poole and her mother. My pretended efforts to solve the mystery of Rathbone's disappearance told. I saw that I was winning back all the ground I had lost. I had great hopes. These seemed to culminate the other night at Lord Malvin's reception. Miss Poole promised to receive me the next day and give me a definite answer. I knew what that meant; it meant yes. I was prepared to stake everything upon it. When I called at Curzon Street in the evening I was told that she was unwell, and could not see me. The next day I succeeded in seeing her. I was taken aback. There was a distinct change in her manner. The old intimacy and freedom which I had been able to re-establish had gone. There was almost a shrinking in her attitude—she seemed afraid of me."

"Well, that is easily accounted for. You have done something hitherto beyond human power. Naturally she regards you as a person apart—some one who can work miracles. But what did she say?"

"It wasn't that sort of shrinking, Guest. I know Miss Poole well. I understand the real strength and brilliancy of her mind. She is not a foolish, ordinary girl to be frightened as you suggest. I told her that I had come for my answer. I think I spoke well. My heart was in what I said, and I urged my cause as powerfully as I could. Miss Poole absolutely refused to give me any answer at all."

"Well, that is no very terrible thing, William. I know little of women, but one is told that is their way. She will not yield at once, that is all."

"I wish I could think so, Guest. It did not strike me in that way at all. And she said a curious thing also. She said that I might re-open the question after the public demonstration. She wouldn't pledge herself to give an answer even then. But she said that I must say nothing more to her on the subject until after the demonstration."

Wilson Guest laughed.

"What a powerful drug this love is!" he said. "It's as unexpected in its action as ether! My dear William, you are worrying yourself about nothing. I'm sure of it. Remember that you can't look at the thing with an unprejudiced eye. It's all quite clear to me. Miss Poole simply wants to wait until she has seen your triumph with her own eyes. That is all, believe me. You are in too much of a hurry. How curious that is! It is the strangest thing in the world to find you—you of all men—in a hurry. It is only by monumental and marvellous patience that you have succeeded in discovering a law, and applying that law with my help, which makes you the greatest man of science the world has ever known. And yet you leap at the fence of a girl's hesitation and reserve as if everything depended on breaking a record for the jump!"

Gouldesbrough smiled faintly and shook his head. He was not convinced, but it was plain that he was comforted by what Guest had said.

His smile was melancholy and gently sad; and in the electric radiance of the huge mysterious room he seemed like some eager and kindly priest or minister who bewailed the sins of his flock, but with a humorous and human understanding of mortal frailty.

And there he stood, the greatest genius of modern times, and also one of the most cruel and criminal of living men. Yet so strange and tortuous is the human soul, so enslaved can conscience be by the abnormal mind, that he thought of himself as nothing but a devoted lover.

His passion and desire for this girl were horrible in their egotism and their intensity alike. But the man with the marvellous brain thought that the one thing which set him apart from the herd and redeemed him for his crime was his love for Marjorie Poole. He really, honestly and truly, believed that!

It was not without reason that Donald Megbie had seen the blaze of insanity in Sir William's eyes. A supreme genius is very seldom sane. Professor Lombroso has said so, Max Nordau agitated scientific Europe by saying it a few years ago.

Yet some one more important said it many years before—

"So the matter rests there?" Guest asked.

"Yes," Sir William answered; "but I have altered the day of the demonstration. There is no need to wait after all! Everything is prepared. I have sent out cards for Friday next, three days from now."

Guest poured out some more of the spirit. He laughed rather contemptuously.

"Can't wait, then!" he said. "I'm glad I'm free from these entanglements, William. Of course it doesn't matter when the people come to see the thing at work. As you say, everything is quite ready. But there is another thing to be considered. What about Rathbone? He's no more use to us now, and he must be got rid of. Shall I go down-stairs and kill him?"

He said it with the indifference with which he might have proposed to wash his hands.