Again the searchlight beam swung out and down, sought the green monster. But this time the Lassan globe acted more quickly. The yellow ray lifted, probed for them, caught them in its beam. Instantly, the occupants of the _Monitor_ felt a racking pain in every joint; the camera-boxes of the gravity-beam trembled in their racks, the windows, set in solid steel though they were, shook in their frames, the whole body of the rocket-ship seemed about to fall apart. * * * * * Desperately Sherman strove with the controls; dived, dodged, then finally, with a raised hand to warn the rest, side-slipped and tumbled toward the earth, pulling out in a swinging curve with all power on--a curve that carried them a good ten miles away before the yellow ray could find them. "Boy!" said Murray Lee, feeling of himself. "I feel as though every joint in my body were loose. What was that, anyway?" "Infra-sound," replied Sherman. "You can't hear it, but it gets you just the same. Like a violinist and a glass. He can break it if he hits the right note. I told you those babies would get something hot. They must have found a way to turn that pure light of theirs into pure sound and vibrate it on every note of the scale all at once, beside a lot the scale never heard of. Well, now we know." "And so do they," said Ben. "That bozo isn't going to hang around and take another chance on getting mashed with our gravity beam. Even if we did only tip him, I'll bet we hurt him plenty." "All I've got to say," replied Sherman, "is that I'm glad we're made of metal instead of flesh and blood. If that infra-sound ray had hit us before, we'd be mashed potatoes in that field down there. No wonder the signal station went out so quick." "Do we go back and take another whack at them?" asked Murray Lee. "I don't like to do it with this ship," Sherman replied. "If we had the _Monitor II_ it would be easy. With that extra vacuum chamber around her, she'll take quite a lot of that infra-sound racket. Vacuum doesn't conduct sound you know, though we'd get some of it through the struts. But this one--. Still I suppose we'll have to show them we mean business." The _Monitor_ turned, pointed her lean prow back toward Newark, and bore down. In their flight from the infra-sound ray the Americans had dived behind a fluffy mass of low-hanging cloud; now they emerged from it, they could see the huge green ball, far up the river, retreating at its best speed. "Aha," Sherman said. "He doesn't like gravity beams on the coco. Well, come on, giddyap horsey. Give her the gun, Murray." Under the tremendous urge of the gravity-beam explosions at her tail, the _Monitor_ shot skyward, leaving a trail of orange puffs in her wake as the beam decomposed the air where it struck it. Sherman lifted her behind the clouds, held the course for a moment, called "Ready, Gloria?" and then dropped.