He set to work on the car seat, pushing the pistol with its three remaining bullets out of the way. The pistol was reserved for Jill in case of untoward events, when it would be of little or no practical value. He operated on the tiny radio with his pocket-knife to establish a circuit which should oscillate when the battery was turned on. There was induction, to raise the voltage at the peaks and troughs of the oscillations. A transistor acted as a valve to make the oscillations repeated surges of current of one sign in the innumerable sharp points of the graters. And there was an effect he did not anticipate. The ion-forming points were of minutely different lengths and patterns, so the radiation inevitably accompanying the ion clouds was of minutely varying wave lengths. The consequence of using the two graters was, of course, that rather astonishing peaks of energy manifested themselves in ultra-microscopic packages for a considerable distance from the device. But Lockley did not plan that. It happened because of the materials he had to use in lieu of something better. When it was finished he told Jill, "I can only check ion production here. If it works, it ought to make a lighter-flame flicker when near the points. If it does that, I'll go up the road to where the trailer-truck stopped. I've a pretty good idea that the road's blocked by a terror beam there." Absorbed, he threw the switch. And instantly there was a racking, deafening explosion. The pistol on the car seat blew itself to bits, smashing the windshield and ripping the cushion open. The three cartridges in its cylinder had exploded simultaneously. Lockley seized a pitchfork. He stood savagely, ready for anything. Powder smoke drifted through the barn. Nothing else happened. After long, tense moments, Lockley said slowly, "That could be another weapon the monsters have turned on. It's been imagined. They could be using a broadcast or a beam we haven't suspected to disarm the troops of the cordon. They could have a detonator beam that sets off explosives at a distance. It's possible. And if that's what they're turning on they only have to sweep the sky and the bombers aloft will be wiped out." But there were no sounds other than the slowly diminishing drip of water from the barn roof, and the house eaves, and the few trees in the barnyard. "Anyhow they've ruined our only weapon," said Lockley coldly. "It would be a detonation beam setting off the cartridges. That would be a perfect protection against atomic bombs, if the chemical explosive that makes them go off could be triggered from a distance. Clever people, these monsters!" Then he said abruptly, "Come on! It's ten times more necessary for us to get to where somebody can make use of our information!" "Go where?" asked Jill, shaken once more.