"It had to be done, of course—it was either them or else all the rest of the Universe," Season said, jerkily. "However, even that fact doesn't make it go down easy. Well, we're done with this projector. From now on it's strictly up to us and Skylark Three. Let's beat it over there and see if they've got her done yet—they were due to finish up today, you know."
It was a silent group who embarked in the little airboat. Half way to their destination, however, Seaton came out of his blue mood with a yell.
"Mart, I've got it! We can give the Lark a lot more acceleration than they are getting—and won't need the assistance of all the minds of Norlamin, either."
"How?"
"By using one of the very heavy metals for fuel. The intensity of the power liberated is a function of atomic weight, or atomic number, and density; but the fact of liberation depends upon atomic configuration—a fact which you and I figured out long ago. However, our figuring didn't go far enough—it couldn't: we didn't know anything then. Copper happens to be the most efficient of the few metals which can be decomposed at all under ordinary excitation—that is, by using an ordinary coil, such as we and the Fenachrone both use. But by using special exciters, sending out all the orders of rays necessary to initiate the disruptive processes, we can use any metal we want to. Osnome has unlimited quantities of the heaviest metals, including radium and uranium. Of course we can't use radium and live—but we can and will use uranium, and that will give us something like four times the acceleration possible with copper. Dunark, what say you snap over there and smelt us a cubic mile of uranium? No—hold it—I'll put a flock of forces on the job. They'll do it quicker, and I'll make 'em deliver the goods. They'll deliver 'em fast, too, believe us—we'll see to that with a ten-ton bar. The uranium bars'll be ready to load tomorrow, and we'll have enough power to chase those birds all the rest of our lives!"
Returning to the projector, Seaton actuated the complex system of forces required for the smelting and transportation of the enormous amount of metal necessary, and as the three men again boarded their aerial conveyance, the power-bar in the projector behind them flared into violet incandescence under the load already put upon it by the new uranium mine in distant Osnome.
The Skylark lay stretched out over two miles of country, exactly as they had last seen her, but now, instead of being water-white, the ten-thousand-foot cruiser of the void was one jointless, seamless structure of sparkling, transparent, purple inoson. Entering one of the open doors, they stepped into an elevator and were whisked upward into the control room, in which a dozen of the aged, white-bearded students of Norlamin were grouped about a banked and tiered mass of keyboards, which Seaton knew must be the operating mechanism of the extraordinarily complete fifth-order projector he had been promised.
"Ah, youngsters, you are just in time. Everything is complete and we are just about to begin loading."
"Sorry, Rovol, but we'll have to make a couple of changes—have to rebuild the exciter or build another one," and Seaton rapidly related what they had learned, and what they had decided to do.