"A little less than twenty-nine miles."
"We must do better than that," said Tom. "I'll use more powder, and try one of the newer shells. I'll elevate the gun a trifle, too."
Again came that terrific report, that trembling of the ground, that concussion, that blast of air as it rushed in to fill the vacuum caused, and then the vibrating echoes.
"I think you must have gone the limit this time, Tom!" yelled Ned, as he turned on the compressed air to blow the powder fumes and unconsumed bits of explosive from the gun tube.
"Possibly," admitted Tom. "Here comes the report." The wireless operator waved a slip of paper.
"Thirty-one miles!" he announced.
"Hurray!" cried Mr. Damon. "Bless my telescope! The longest shot on record!"
"I believe it is," admitted the chief of the ordnance department. "I congratulate you, Mr. Swift."
"I think I can do better than that," declared Tom, after looking at the various recording gauges, and noting the elevation of the gun. "I think I can get a little flatter trajectory, and that will give a greater distance. I'm going to try."
"Does that mean more powder, Tom?" asked Ned.