"We got through Io's energy barrage!" he shouted wildly. "We did that much, at least; and for a moment, when our Penetrator went wrong, I didn't think our luck would be even that good."
Evan Harwich leered back at the youth, from near the now useless apparatus that John Arnold had invented. "Yes, we got through," he grunted hoarsely. "The energy shell must be only a couple of thousand miles thick, with free space underneath, between it and Io itself. The Gyon condenser kept working raggedly just long enough to get us out of the danger zone, without being completely blown apart!"
Harwich didn't have to test the controls of the ship to know that they were useless, now. The rockets were silent too. The RQ257 was falling free toward the Forbidden Moon, still a couple of thousand miles beneath.
"But dammit, Evan!" young Arnold growled. "The Gyon condenser shouldn't have quit on us at all! Those things are tested for heavy loads of power!"
The patrol pilot was well aware of that. Clinging to the base of the Penetrator, he was close enough to see detail. The lights in the cabin had gone out, but the ugly effulgence of Io was streaming through the windows.
Projecting from the shattered bakelite box of the Gyon condenser, were two slender, bent wires that should have been joined together. It had been one wire once, but it had snapped in the middle.
The ends were faintly scorched and blued; but there was something else, too. They were bevelled off curiously, as if they had been notched.
"Cut with a file!" Harwich fairly snarled. "The wire was cut with a file. Then the insulation was rewrapped carefully so that all the evidence was hidden!"
The cause of the accident was plain. The wire had been able to carry the load of power easily enough during the tests; but under the additional load of fighting the Ionian hell-zone, it had burned through and snapped!
"Bayley!" Paul Arnold whispered in the ominous stillness that now pervaded the plummeting derelict of the RQ257. "He brought the condenser, you remember! Evan, I know you were careful to watch everything he did during the assembly and tests in the lab itself. He must have had the Gyon condenser at his apartment before he brought it to us. He must have doctored it there! He was planning even then to get rid of me! And when he found you around, he decided that he wouldn't weep if he got rid of you too!"