The big dome above was cut in sections and removed, and then the sky could be seen all the way from the bottom of the ship where the pilot's greenhouse should have been. Channing looked it over and then remarked: "All we need now is an electron collector." "I thought you wanted to shoot 'em off," objected Hadley. "I do. But we've got to have a source of supply. You can't toss baseballs off of the Transplanet Building in Northern Landing all afternoon, you know, without having a few brought to you now and then. Where do you think they come from?" "Hadn't thought of it in that way. What'd happen?" "We'd get along for the first umpty-gillion electrons, and then all the soup we could pack on would be equalized by the positive charge on the ship and we couldn't shoot out any more until we got bombarded by the sun--and that bombardment is nothing to write home about as goes quantity. What we need is a selective solar intake plate of goodly proportions." "We could use a mental telepathy expert, too. Or one of those new beams that Baler and Carroll dug up out of the Martian desert. I've heard that those things will actually suck power out of any source, and bend beams so as to enter the intake vent, or end." "We haven't one of those, either. Fact of the matter is," grinned Channing ruefully, "we haven't much of anything but our wits." "Unarmed, practically," laughed Hadley. "Half armed, at least. Ah, for something to soak up electrons. I'm now wondering if this electron gun is such a good idea." "Might squirt some protons out the other direction," offered Hadley. "That would leave us without either," said Don. "We'd be like the man who tossed baseballs off of one side and himself off the other--Hey! Of course we have some to spare. We can cram electrons out of the business end, thus stripping the planetary rings from the atoms in our cathode. From the far side we'll shoot the canal rays, which in effect will be squirting protons, or the nuclei. Since the planetaries have left for the front, it shouldn't be hard to take the protons away, leaving nothing. At our present voltages, we might be able to do it." Channing began to figure again, and he came up with another set of anodes to be placed beyond the cathode. "We'll ventilate the cathode and hang these negative electrodes on the far side. They will attract the protons, impelled also by the positive charge on the front end. We'll maintain a balance that way, effectively throwing away the whole atomic structure of the cathode. The latter will fade, just as the cathodes do in the driving tubes, only we'll be using electronic power instead of sub-electronic. Y'know, Hadley, some day someone is going to find a way to detect the--we'll call it radiation for want of anything better--of the driver. And then there will open an entirely new field of energy. I don't think that anybody has done more about the so-called sub-electronic field than to make a nice, efficient driving device out of it.