She saw that something unusual had occurred, for Tom was working frantically at the mechanism in front of him.
But, in spite of this, he seemed aware that Mary was in danger, not so much, perhaps, from what might happen to the machine, as what she might do in her terror.
"Oh! Oh!" cried the girl, and Tom heard her above the terrific noise of the motor, for she was speaking with her lips close to the tube that served as a sort of inter-communicating telephone for the craft. "Oh, we are falling! I'm going to jump!"
"Sit still! Sit still for your life!" cried Tom Swift. "I'll save you all right! Only sit still! Don't jump!"
Mary, her red cheeks white, sank back, and the young inventor redoubled his efforts at the controls and other mechanisms.
