The young inventor and his friends, once more in possession of their airship, lost little time in planning to return. They found that the spies were all expert aeronauts, and had kept a careful chart of their location. They were then halfway across the Atlantic, and in a short time longer would probably have been in some foreign country. But Tom turned the Mars about.
The craft had only been slightly damaged by the lightning bolt, though three of the gas bag compartments were torn, The others sufficed, however, to make the ship sufficiently buoyant.
When morning came Tom and his friends had matters running almost as smoothly as before their capture.
The prisoners had no chance to escape, and, indeed, they seemed to have been broken in spirit. La Foy was no longer the insolent, mocking Frenchman that he had been, and the two chief foreign engineers seemed to have lost some of their reason when the lightning struck them.
"But it was a mighty lucky and narrow escape for us," said Ned, as he and Tom sat in the pilot-house the second day of the return trip.
"That's right," agreed his chum.
Once again they were above the earth, and, desiring to get rid as soon as possible of the presence of the spies, a landing was made near New York City, and the government authorities communicated with. Captain Warner and Lieutenant Marbury took charge of the prisoners, with some Secret Service men, and the foreigners were soon safely locked up.
"And now what are you going to do, Tom?" asked Ned, when, once more, they had the airship to themselves.
"I'm going back to Shopton, fix up the gas bag, and give her another government trial," was the answer.
And, in due time, this was done. Tom added some improvements to the aircraft, making it better than ever, and when she was given the test required by the government, she was an unqualified success, and the rights to the Mars were purchased for a large sum. In sailing, and in the matter of guns and bombs, Tom's craft answered every test.