"You see, the rocket is the freely suspended frame," he went on, "while this lever controls a gyroscopic wheel somewhere. To set it spinning to the right causes us to turn to the left, and vice versa."
"But you almost stood us on our heads, a moment ago! How did that happen?"
"Simply because I threw the lever too far to the right. We are in interstellar space, obviously, where every change of direction involves an adjustment of equilibrium."
And if Stoddard didn't exactly understand, being first a secret service man and only secondarily a scientist, at least he showed his ignorance no further. If the professor could bring this astounding machine back to Earth, that was all he wanted.
Prescott said he could, he thought, providing they had fuel enough left. So for the next few minutes, while the younger man held his breath, the professor labored with the various instruments on that complicated dial.
"Now then, I think we're headed back," he said at length, relaxing. "But we've got to have visibility, otherwise we will land with a velocity of about twenty thousand miles an hour, which is what I figure we're making at the present time."
"Good Lord!" gasped Stoddard. "I'll say we've got to have visibility! Wait a minute! Let me look around!"
He searched the room for further instruments--to find nothing that in any way met the purpose.
But even as he returned dejected, the professor cried out:
"Here--I've got it! Take a look at this!"
Bending over a small table beside the dial, Stoddard saw mirrored, in its ground-glass surface a hazy circular panorama that at first had no significance. But as he continued to peer down upon the scene, certain familiar aspects loomed out. It was the Earth--and what he was looking at was a view of the North and South American continents!
For some moments Stoddard stared at this amazing panorama in silence; saw it grow rapidly clearer, as the careening rocket plunged like a giant shell toward the earth.
"My God!" he whispered at length in awe. "Do you think you can ever check our speed?"
"I think so," the professor replied, busy over his instruments. "But where do we want to land? How do we know what state we were in?"
Whereupon Stoddard told him of that Texas license plate.