Page:Amazing Stories Volume 07 Number 08.djvu/39

of the missive, hoping that it would not consist of the usual concoction of incorrect science and fantastic nonsense.

When I had finished, I was not sure whether it was nonsense or not. Here is a digest of the contents:

Dane first gave an account of himself, mainly, as he said, to show that he ought to know what he was talking about. He had been a professor of physics at one of the larger universities for about twenty years. During and before this time, he had ceaselessly experimented upon atomic construction, trying to find a way to release the tremendous stores of sub-atomic energy present in all matter. In this he had been unsuccessful.

In the course of hit work, however, he had discovered a means of generating a gravity field of peculiar construction. This consisted of a central sphere of no gravity, and outside of that, a region of inward radial attraction. This field did not obey the usual inverse square law, but was instead almost constant between an inner sphere of no attraction and an outer sphere at which the force was cut off abruptly. The radius of the inner sphere and the thickness of the gravitational shell could be set at any convenient value by suitable adjustment.

At this point I came very close to putting the thing aside in disgust. This man must be an idiot. In these times, working upon atomic disintegration has taken the place of the old perpetual motion search, as an amusement for fools. All the prominent physicists have pronounced it impossible.

About the only thing that could be more nearly impossible, if one can compare the relative impossibilities of things that are quite impossible, would be the creating of an artificial gravitational field. And this Professor Dane had worked with the one, and actually claimed to have produced the other!

I continued to read, mainly to see what other extravagant claims he would make. But as I read, I began to revise my early estimate of Dane's scientific knowledge. The rest of the document took up the problem of the generation of the gravitational field, and gave a solution for the power required, gravitational potential, and time retardation. His reasoning and mathematics were brilliant, but conservative and correct. After he had solved a few problems that had baffled the scientists of the world for a century, and with which I was familiar enough to realize that the solutions were right, I began to wonder whether Dane might not possibly be the only one of us in step with the truth.

When I had finished, there was no longer any doubt in my mind. I would visit Dane in his laboratory, and see whether he could make good his promise to give me an actual demonstration of the gravity field and its time effect. I also made up my mind to find out why Dane believed that atomic power was obtainable.

Visiting Dane was not the simple matter it would have been before the war. The enemy considered me personally responsible for the stopping of their early victorious march, and my movements were watched. There had been several attempts to kill me.

As it was, two courses were open—to go alone and secretly or to arrange for a heavy guard during my visit. Both methods entailed risks.

If I took a guard, the enemy would almost certainly get word of my activities, for a number of recent incidents seemed to indicate that an appreciable fraction of our army was composed of enemy spies. The laboratory would then become a rendezvous for the most talented of the enemy intelligence, and they would hinder our work, or perhaps even obtain Dane’s secret, always provided there was anything in this time machine business.

On the other hand, if I went alone, the laboratory would be unprotected, and if spies did succeed in tracing me, they could easily dispose of Dane and myself, and examine our equipment at leisure.

The risks balanced up about evenly, but I finally decided in favor of solitary secrecy. As a measure of precaution, I did not notify Dane of my coming, but I was sure that, with the explicit directions he had given in his letter, there would be no difficulty in locating the abandoned farmhouse near the Niagara Falls in which he had set up his laboratory. My plan was to fly from the Capitol, located in Saint Louis after the burning of Washington, direct to Dane’s laboratory. The start was to be made when the moon, lacking about four days from the full, set that night.

Meanwhile, I did some figuring upon the time effect of a field such as Dane claimed to create. The fundamental principle of this effect is of course well known. Fifty years before, when Einstein first proposed his theory of general relativity, he predicted, from the theory, that time upon the surface of the sun, a point of high gravitational potential, was slower than time in fieldless space or at a point of lesser gravitational potential, such as the surface of the earth. This proposition, being readily amenable to practical test, was definitely verified by a series of spectroscopic test^[1] made between 1919 and 1928, and was one of the practical proofs of the truth of the theory.

One point admitted of no dispute—if Dane could generate a field of sufficient strength he could slow time inside the field to any desired fraction of the normal time outside. By placing a living creature in this region of retarded time, this creature, living and aging only a day, would find, upon emerging, a world that had aged thousands of years. This time travel could present no paradox, for it would be in the strictest sense actually possible, and the workings of a natural law cannot be paradoxical.

However, this sort of time travel could not be very useful, unless one preferred to spend the remainder of his life in the far future. There would be no way of getting information back from the future to the present, because the process was not one that could be reversed, but operated strictly in one direction only. Yet it was plain enough that whatever Dane had worked out must be reversible. That was certainly the only sort of time machine that could be of use in the present.