which increased immensely with the radioactive changes that followed.
If the charge-concentration remained at the points of Pumping, the effect on the orbit-distorted atoms being Pumped would stop the entire process almost at once, but of course, there was diffusion to take into account. The charge-concentration diffused outward over the Earth, and the effect on the Pumping process had been calculated with that in mind.
The increased positive charge of the Earth generally forced the positively charged Solar wind to avoid the planet at a greater distance, and the magnetosphere was enlarged. Thanks to the work of McFarland (the real originator of the Great Insight according to Lamont) it could be shown that a definite equilibrium point was reached as the Solar wind swept away more and more of the accumulating positive particles that were repelled from Earth’s surface and driven higher into the exosphere. With each increase in Pumping intensity; with each additional Pumping Station constructed, the net positive charge on Earth increased slightly, and the magnetosphere expanded by a few miles. The change, however, was minor, and the positive charge was, in the end, swept away by the Solar wind and spread through the outer reaches of the Solar system.
Even so—even allowing for the most rapid possible diffusion of the charge, the time would come when the local charge-difference between Universe and para-Universe at the points of Pumping would grow large enough to end the process, and that would be a small fraction of the time it would take really to use up all the electrons; roughly, a trillion-trillionth of the time.
But that still meant that Pumping would remain possible for a trillion years. Only a single trillion years, but that was enough; it would suffice. A trillion years was far longer than man would last, or the Solar system either. And if man somehow did last that long (or some creature that was man’s successor and supplanter) then no doubt something would be devised to correct the situation. A great deal could be done in a trillion years.
Lamont had to agree to that.
But then he thought of something else, another line of thought that he well remembered Hallam himself had dealt with in one of the articles he had written for popular consumption. With some distaste, he dug out the article. It was important to see what Hallam had said before he carried the matter further.
The article said, in part, “Because of the ever-present gravitational force, we have come to associate the phrase ‘downhill’ with the kind of inevitable change we can use to produce energy of the sort we can change into useful work. It is the water running downhill that, in past centuries, turned wheels which in turn powered machinery such as pumps and generators. But what happens when all the water has run downhill?
“There can then be no further work possible till the water has been returned uphill—and that takes work. It fact, it takes more work to force the water uphill than we can collect by then allowing it to flow downhill. We work at an energy-loss. Fortunately, the Sun does the work for us. It evaporates the oceans so that water vapor climbs high in the atmosphere, forms clouds, and eventually falls again as rain or snow. This soaks the ground at all levels, fills the springs and streams, and keeps the water forever running downhill.
“But not quite forever. The Sun can raise the water vapor, but only because, in a nuclear sense, it is running downhill, too. It is running downhill at a rate immensely greater than any Earthly river can manage, and when all of it has run downhill there will be nothing we know of to pull it uphill again.
“All sources of energy in our Universe run down. We can’t help that. Everything is downhill in just one direction, and we can force a temporary uphill, backward, only by taking advantage of some greater downhill in the vicinity. If we want useful energy forever, we need a road that is downhill both ways. That is a paradox in our Universe; it stands to reason that whatever is downhill one way is uphill going back.
“But need we confine ourselves to our Universe alone? Think of the para-Universe. It has roads, too, that are downhill in one direction and uphill in the other. Those roads, however, don’t fit in with our roads. It is possible to take a road from the para-Universe to our Universe that is downhill, but which, when we follow