the year 2,952," came the answer, "the earth succeeded in getting into communication with Mars. Radio pictures were sent back and forth between the two worlds until they learned each other's languages; then sound communication was established. The Martians had been trying to signal the earth since the beginning of the twentieth century, but were unable to set up a system of communication because of the insufficient scientific advancement of the Earthmen.
"About a thousand years later, a message was received from Venus, which had now advanced to the earth's state of civilization, when Mars was signalled. For nearly five hundred years they had been receiving messages from both the earth and Mars, but had been unable to answer.
"A little over five thousand years later, a series of sounds was received which seemed to come from somewhere beyond Venus. Venus and Mars heard them too; but, like us, were able to make nothing of them. All three worlds broadcasted their radio pictures on the wave length corresponding to that of the mysterious sounds, but received no answer. At last Venus advanced the theory that the sounds had come from Mercury, whose inhabitants, obliged to live upon the side of their world farther from the sun, would be either entirely without sight or with eyes not sufficiently developed to see our pictures.
"Recently something dire has happened to Mars. Our last messages from her told of terrible wars and pestilences, such as we are now having upon earth. Also, her water supply was beginning to give out, due to the fact that she was obliged to use much of it in the manufacture of atmosphere. Suddenly, about fifty years ago, all messages from her ceased; and upon signalling her, we received no answer."
Mortimer covered the transmitter with his hand. "That," he said to me, "can mean only that intelligent life upon Mars had become extinct. The earth, then, can have but a few thousand years yet to go."
For nearly an hour longer he quizzed Williams upon conditions of the year 46,812. All the answers showed that while scientific knowledge had reached an almost incredulous stage of advancement, the race of mankind was in its twilight. Wars had killed off thousands of people, while strange, new diseases found hosts of victims daily in a race whose members were no longer physically constituted to withstand them. Worst of all, the birth rate was rapidly diminishing.
"Listen to me." Mortimer raised his voice as if to impress his invisible subject with what he was about to say. "You are now living in the second day. Tell me what you see."
There was a moment or so of silence; then the voice, keyed even higher than before, spoke again.
"I see humanity in its death-throes," it said. "Only a few scattered tribes remain to roam over the deserted continents. The cattle have begun to sicken and die; and it is unsafe to use them for food. Four thousand years ago, we took to the manufacture of artificial air, as did the Martians before us. But it is hardly worth while, for children are no longer born. We shall be the last of our race."
"Have you received no recent word from Mars?" asked Mortimer.
"None. Two years ago, at her proper season, Mars failed to appear in the heavens. As to what has become of her, we can only conjecture."
There was a horrible suggestiveness about this statement. I shuddered, and noticed that Mortimer did, also.
"The Polar Ice Cap has begun to retreat," resumed the voice. "Now it is winters that are short. Tropical plants have begun to appear in the temperate zones. The lower forms of animal life are becoming more numerous, and have begun to pursue man as man once pursued them. The days of the human race are definitely numbered. We are a band of strangers upon our own world."
"Listen to me," said Mortimer again. "It is now the third day. Describe it."
Followed the usual short interval of silence; then came the voice, fairly brittle with freezing terror.
"Why," it screamed, "do you keep me here: the last living man upon a dying planet? The world is festering with dead things. Let me be dead with them."
"Mortimer," I interrupted, "this is awful! Hasn't your experiment gone far enough?"
He pushed back his chair and rose. "Yes," he said, a bit shakily, I thought. "For the present, at least. Come; I will awaken Williams."
I followed him down the hall, and was close upon his heels, when he flung open the door of the lead-lined room, and stepped inside. Our cries of surprised alarm were simultaneous.
In the chair where we had left him sat Williams; but physically he was a different man. He had shrunken several inches in stature, while his head appeared to have grown larger, with the forehead almost bulbous in aspect. His fingers were extremely long and sensitive, but suggestive of great strength. His frame was thin to emaciation.
"Good Heavens!" I gasped. "What has happened?"
"It is an extreme case of mental influence upon matter," answered Mortimer, bending over the hypnotized man. "You remember how young Bennet's features took on the characteristics of a Hun? A similar thing, but in a much intenser degree, has happened to Williams. He has become a man of the future physically as well as mentally."
"Good Lord!" I cried. "Waken him at once! This is horrible."
"To be frank with you," said Mortimer gravely, "I am afraid to. He has been in this state much longer than I realized. To waken him too suddenly would be dangerous. It might even prove fatal."
For a moment he seemed lost in thought. Then he removed the ear phones from Williams' head, and addressed him. "Sleep," he commanded. "Sleep soundly and naturally. When you have rested sufficiently, you will awaken and be your normal self."
Shortly after this, I left Mortimer, and, although it was my day off duty, went to my hospital. How good my commonplace tonsil cases seemed after the unholy things I had just experienced! I surprised the resident physician almost into a state of coma by putting in the remainder of the day in the hardest work possible in the free clinic; and finally went home, tired in mind and body.
I turned in early for what I deemed a well-earned rest, and fell asleep instantly. The next thing of which I was conscious was the insistent ringing of the telephone bell beside my bed.
"Hello," I cried sleepily, taking down the receiver. "Dr. Claybridge speaking."
"Claybridge, this is Mortimer," came the almost hysterical response. "For God's sake, come over to the laboratory at once!"
"What has happened?" I demanded, instantly wide awake. It would take something unusual to wring such excitement from the unemotional Mortimer.
"It's Williams," he answered. "I can't bring him back. He got awake about an hour ago, and still believes that he is living in the future. Physically, he is the same as he was when last you saw him this afternoon."
"I'll be over at once," I fairly shouted, and slammed the receiver down upon its hook. As I scrambled into my clothes, I glanced at the clock. Two fifteen. In half an hour I could reach the laboratory. What would I find waiting for me?
Mortimer was in the lead room with Williams when I arrived.
"Claybridge," he said, "l need someone else's opinion in this case. Look at him, and tell me what you think."
Williams still occupied the chair in the middle of the room. His eyes were wide open, but it was plain that he saw neither Mortimer nor me. Even when I bent over him and touched him, he gave no sign of being conscious of my presence.
"He looks as if he were suffering from some sort of catalepsy," I said, "yet his temperature and pulse are
