There were two compartments–one under the sleeping room floor in which stood the mechanism for running the Terror, and the other beneath the store room floor, in which stood a small powerful dynamo which operated automatically by a spring clockwork.
All the room lamps and the search-light derived their current from the dynamo, while it worked the motor, and that in turn operated the driving wheel machinery.
"It don't require a skilled electrician to see how the Terror operates." said Jack, as he showed the sheriff the interior, "for I have based her construction upon the simplest known principles."
"Oh, I can readily see how she ought to work." "I'll give you an example," said Jack, seating himself behind the steering wheel and pulling a lever.
That set the clockwork in motion, it spun the dynamo armature, a current was generated, flashed into the motor, the shaft operated the machinery, and the Terror rolled ahead.
When she reached the end of the room he reversed the lever and she backed to the other wall.
He then ran her around the room in a circle, steering by the wheel, and attained a tremendous velocity; he put on the brakes and she stopped within a few feet, and he turned a switch that caused the search-light and lamps in her to glow.
By the time he finished the sheriff was wild with admiration of the extraordinary vehicle.
"For what purpose did you build her? he asked Jack, when they finished maneuvering her, and alighted.
"Just for fun, I have plenty of money and leisure, and a strong liking for building these electrical inventions."