We drove in Leonora's car through London. The streets were crowded. I do not think that much routine work was done that day. People formed little crowds on the pavements, and at Oxford Circus someone was speaking to a large concourse from the seat of a motor lorry.

Leonora seemed extraordinarily apathetic. She leaned back in the car and seemed uninterested in the passing scene. Sarakoff, wrapped up in a fur rug, stared dreamily in front of him. As far as I can recall them, my feelings during that swift tour of London were vague. The buildings, the people, the familiar signs in the streets, the shop windows, all seemed to have lost in some degree the quality of reality. I was detached from them; and whenever I made an effort to rouse myself, the ugliness and meaninglessness of everything I saw seemed strangely emphasized.

When we reached Harley Street we found my house little damaged, save for a broken panel in the green front door and a few panes of glass smashed in the lower windows. The house was empty. The servants had vanished.

Leonora said she wished to go home and she drove off in the car. Sarakoff did not even wave farewell to her, but went straight up to his room and lay down on the bed. I went into the study and sat in my chair by the fireplace.

I was roused by the opening of the door, and looking up I saw a face that I recognized, but for the moment I could not fit a name to it. My visitor came in calmly, and sat down opposite me.

"My name is Thornduck," he said. "I came to consult you about my health a few days ago."

"I remember," I said.

"Your front door was open so I walked in."

I nodded. His eyes, stained with blue, rested on me.

"I have been thinking," he said. "It struck me that there was something you forgot to tell me the other day."

I nodded again.

"You began, if you remember, by asking me if I believed in miracles. That set me thinking, and as I saw your name in the paper, connected with the Blue Disease, I knew you were a miracle-monger. How did you do it?"

"I don't know. It was all due to my black cat. Tripped over it, got concussion and regained my senses with the idea that led up to the germ."

He smiled.

"A black cat," he mused. "I wonder if it's all black magic?"

"That's what Hammer suggested. I don't know what kind of magic it is."

"Of course it is magic," said Thornduck.

"Magic?"

"Of course. Have you even thought what kind of magic it is?"

"No."

"A big magic, such as you have worked, is just bringing the distant future into the present with a rush."

"Sarakoff had some such idea," I murmured. "He spoke of anticipating our evolution by centuries at one stroke."

"Exactly. That's magic. The question remains—is it black magic?" He crossed his thin legs and leaned back in the chair. "I got the Blue Disease the day before yesterday and since then I've thought more than I have ever done in all my life. When I read in the paper this morning that you said the Blue Disease conferred immortality on people I was not surprised. I had come to the same conclusion in a roundabout way. But I want to ask you one question. Did you know beforehand that it killed desire?"

"No. Neither Sarakoff nor I foresaw that."

"Well, if you had let me into your confidence before I could have told you that right away in the general principle contained in the saying that you can't eat your cake and have it. It's just another aspect of the law of the conservation of energy, isn't it?"

"I always had a doubt——"

"Naturally. It's intuitional. The laws of the universe are just intuitions put into words. You've carried out an enormous spiritual experiment to prove what all religions have always asserted however obscurely. All religion teaches that you can't eat your cake and have it. That's the essence of religion, and you, formerly a cut-and-dried scientist, have gone and proved it to the whole world for eternity. Rather odd, isn't it?"

I watched his face with interest. It was thin and the complexion was transparent. His eyes, wonderfully wide and brilliantly stained by the germ, produced in me a new sensation. It was akin to enthusiasm, but in it was something of love, such as I had never experienced for any man. I became uplifted. My whole being began to vibrate to some strangely delicate and exquisite influence, and I knew that Thornduck was the medium through which these impulses reached me. It was not his words but the atmosphere round him that raised me temporarily to this degree of receptivity.

"It is odd," I said.

He continued to look at me.

"You have a message for me?" I observed at last.

"Why, yes, I have," he replied. "You have done wrong, Harden. You have worked black magic, and it will fail out of sheer necessity."

"Tell me what I have done."

"You have artificially produced a condition of life many ages before humanity is ready to receive it. The body of desire is being worked up by endless labour into something more delicate and sensitive—into a transmutation that we can only dimly understand. At present the whole plot of life is based on the principle of desire and in this way people are kept busy, constantly spurred on to thought and activity by essentially selfish motives. It is only in abstract thought that the selfless ideal has a real place as yet, but the very fact that it is there shows what lies at the top of the ladder that humanity is so painfully climbing. As long as desire is the plot of life, death is necessary, for its terrible shadow sharpens desire and makes the prizes more alluring and the struggle more desperate. And so man goes on, ceaselessly active and striving, for without activity and striving there is no perfecting of the instrument. You can't have upward progress in conditions of stagnation. All that strange incredible side of life, called the Devil, is the inner plot of life that makes the wheels go round and evolution possible. It is vitally necessary to keep the vast machinery running at the present level of evolution. Desire is the furnace in the engine-house. The wheels go round and the fabric is slowly and intricately spun and only pessimists and bigots fail to see evidence of any purpose in it all. Now what has your Blue Disease done? It has taken the whole plot out of life at its present stage of development at one fell swoop. It has killed Desire—put out the furnace before the pattern in the fabric is nearly complete."

"But I never could see that, Thornduck. How could I foresee that?"

"If you had had a grain of vision you would have known that you couldn't give humanity the gift of immortality without some compensatory loss. The law of compensation is as sure as the law of gravity—you ought to know that."

"I had dim feelings—I knew Sarakoff was wrong, with his dream of physical bliss—but how could I foresee that desire would go?"

"As a mere scientist, test-tube in hand, you couldn't. But you're better than that. You've got a glimmering of moral imagination in you."

He fell into a reverie.

"You are keeping something back. Tell me plainly what you mean," I asked.

"Don't you see that if the germ lasts any length of time," he said, "the machinery will run down and—stop?"