"All right, dad," responded Jack, and altered the course of the Wondership.
Rayburn was a small village some twenty-five miles to the north of Nestorville. Jack kept the receivers on his ears as he flew along. From time to time he exchanged conversation with his father. So far everything appeared to be working as if there were no limit to the distance over which the voices from the air and land could converse.
But suddenly there came a startling interruption to the experiments.
Jack felt a sharp "Bang" at his ears as if a small cannon had been fired close at hand.
CHAPTER VIII.
TALKING THROUGH SPACE.
As the distance increased between air and land stations, the currents became stronger, and frequent tuning was necessary. But Jack was able to keep up a constant conversation with his father, telling him all the details of the country as they flew along. The sudden explosion, however, for it sounded like nothing else, startled him into a sharp exclamation.
"What in the world was that?"