, as if unable to
comprehend it. "My gun burst--it is impossible!"

"But it did," spoke Admiral Woodburn, softly. "Come, you had better see
the surgeon. You may be more seriously injured than you think."

"Was anyone else hurt?" asked the inventor, listlessly. He seemed to
have lost all interest, for the time being.

"No one seriously, as far as we can learn," was the answer.

"What of the man who fired the gun?" inquired the General.

"He was blown high into the air," said Tom. "I saw him."

"But he is not injured beyond some bruises," put in one of the
ambulance surgeons. "We have taken him to the hospital. He fell on a
pile of bags that had held concrete, and they saved him. It was a
miraculous escape."

"I am glad of it," said General Waller. "It is bad enough to feel that
I made some mistake, causing the gun to burst; but I would never cease
to reproach myself if I felt that the man who fired it was killed, or
even hurt."

His friends led him away, and Tom and Ned went over to look at what
remained of the great gun. Truly, the powder, expending its force in a
direction not meant for it, had done terrific havoc. Even part of the
solid concrete bed of the barbette had been torn up.

An official inquiry was at once started, and, while it would take some
time to complete it (for the parts of the gun remaining were to be
subjected to an exhaustive test to determine the cause of the
weakness), it was found that there was some defect in the wiring and
battery that was used to fire the charge.

The soldier who was to press the button was sure he had not done so, as
he had been ordered to wait until General Waller gave the signal from
the bomb-proof. But the gun went off before its inventor reached that
place of safety. Just what had caused the premature discharge could
never be learned, as part of the firing apparatus had been blown to
atoms.

"Well, Tom, what do you think of it?" asked Ned, who had now fully
recovered from the shock. The two were about to leave the proving
grounds, having seen all that they cared to.

"I don't know just what to think," was the answer. "It sure was a big
explosion, and it goes to prove that, no matter how many calculations
you make, when you try a new powder in a new gun you don't know what's
going to happen, until after it has happened--and then it's too late.
It's a big problem, Ned."

"Do you think you can solve it? Are you still going on with your plan
to build the bi