"What's the matter with that airplane?" asked Gloria, pointing to the catapult between the funnels, where a couple of blue-visaged sailors had taken the covering from a seaplane and were giving it a morning bath. The captain looked at Ben. "There may be something in that idea. What do you say to a scout around? I'll let you or one of your people go as an observer." "Tickled to death," Ben replied. "We never got beyond the upper part of the city ourselves. The dodos were too dangerous. I'd like to find out what it's all about." "How about me?" offered Gloria. "Nothing doing, kid. You get left this time. If those birds get after us we may land in the bay with a bump and I don't want this party to lose its little sunshine." "Up anchor!" came the command. "Revolutions for ten knots speed.... I'm going to head down the bay," he explained to the colonists. "If anything happens I want to have sea-room, particularly if they try bombing us." Fifteen minutes later, with the _Brisbane_ running into the morning land-breeze in an ocean smooth as glass, the catapult let go and Ben and the pilot--a lad whose cheeks would have been rosy before the comet, but were now a vivid blue--were shot into the air. Beneath them the panorama of New York harbor lay spread; more silent than it had been at any day since Hendrick Hudson brought his high-pooped galleys into it. As they rose, Ben could make out the line of the river shining through the pearly haze like a silver ribbon; the towers of the city tilted, then swung toward them as the aviator swept down nearer for an examination. Everything seemed normal save at the north and east, where a faint smoky mist still lingered over the buildings they had occupied. Of birds, or of other human occupation than their own, there was no slightest sign. A faint shout was borne to his ears above the roar of the motor and he saw the pilot motioning toward a set of earphones. "What do you say, old chap?" asked the pilot when he had clamped them on. "What direction shall we explore?" Ben glanced down and around. The cruiser seemed to hang in the water, a tiny droplet of foam at her bow the only sign she was still in motion. "Let's go up the Hudson," he suggested. "They seemed to come from that direction." "Check," called the pilot, manipulating his controls. The airplane climbed, swung and went on. They were over Yonkers; Ben could see a river steamer at the dock, where she had made her last halt. "Throw in that switch ahead of you," came through the earphones. "The one marked RF. That's the radiophone for communicating with the ship. We may need it." "O.K.," said Ben.... "Hello.... Yes, this is Ruby, in the airplane. Nothing to report. Everything serene. We're going to explore farther up the river."