Chapter II. A New Idea

Any one who has taken a flight in an aeroplane or gone up in a balloon, will know exactly how Mary Nestor felt on this, her first sky ride of any distance. For a moment, as she looked over the side of the machine, she had a distinct impression, not that she was going up, but that some one had pulled the earth down from beneath her and, at the same time, given her a shove off into space. Such is the first sensation of going aloft. Then the rush of air all about her, the slightly swaying motion of the craft, and the vibration caused by the motor took her attention. But the sensation of the earth dropping away from beneath her remained with Mary for some time.

This sensation is much greater in a balloon than in an aeroplane, for a balloon, unless there is a strong wind blowing, goes straight up, while an aeroplane ascends on a long slant, and always into the teeth of the wind, to take advantage of its lifting power on the underside of the planes. The reason for this sensation--that of the earth's dropping down, instead of one's feeling, what really happens, that one is ascending--is because there are no objects by which comparison can be made. If one starts off on the earth's surface at slow, or at great speed, one passes stationary objects--houses, posts, trees, and the like-- and judges the speed by the rapidity with which these are left behind.

Going up is unlike this. There is nothing to pass. One simply cleaves the air, and only as it rushes past can one be sure of movement. And as the air is void of color and form, there is no sensation of passing anything.

So Mary Nestor, as she shot into the air with Tom Swift, had a sensation as though the earth were dropping from beneath her. For a moment she felt as though she were in some vast void--floating in space--and she had a great fear. Then she calmed herself. She looked at Tom sitting in front of her. Of course, all she could see was his back, but it looked to be a very sturdy back, indeed, and he sat there in the aircraft as calmly as though in a chair on the ground. Then Mary took courage, and ceased to grasp the sides of the cockpit with a grip that stiffened all her muscles. She was beginning to "find herself."

On and on, and up and up, went Mary and Tom, in this the girl's first big sky ride. The earth below seemed farther and farther away. The wide, green fields became little emerald squares, and the houses like those in a toy Noah's ark.

Down below, Mr. Wakefield Damon, who had hurried over from his home in Waterfield to see Tom Swift, gazed aloft at the fast disappearing aeroplane and its passengers.

"Bless my coal bin!" cried the eccentric man, "but Tom is in a hurry this morning. Too bad he couldn't have stopped and spoken to me. It might have been greatly to his advantage. But I suppose I shall have to wait."

"You want to see Master?" asked a voice behind Mr. Damon,