it out into the middle of the street. She was, of course, sorry the moment she had done it, for this was the fifth-story window, and there was a stone pavement below. She looked out in agony, expecting to see the poor beast crushed to death by his fall; but—would you believe it!—that cat coolly turned around in the air, fell right side up on his four paws, and disappeared like a streak of lightning, without being hurt in the least!
"Now, that cat was a great deal worse off than I shall be, because he had nothing to hold on to, while I can cling to the car. I suppose that Dr. Giles has got a mattress fastened to the floor, and by holding on to this I shall be all right."
Dr. Giles had been listening to this entire dialogue with an amused face, but he now thought it time to interfere.
"I think that neither of you has the faintest idea of the conditions that will prevail during the trip," he observed pleasantly. "If you imagine that your fall through the earth is going to be like the fall of a cat through the air, you are very much mistaken, and it will therefore perhaps be well for me to give you some idea of what will really take place. To begin with, I want
