ing on a projectile weighing two tons and a half, would do, and how far it would shoot it."
"Bless my differential gear!" cried Mr. Damon. "A projectile weighing two and a half tons! Tom, it's impossible!"
"That's what General Waller said about his gun; but it burst, just the same," declared Ned. "Poor man, I felt sorry for him. He seemed rather put out at you, Tom."
"I guess he was—a bit—though I didn't mean anything disrespectful in what I said. But now we'll have this test. Koku, take the rest of this powder back. I'll only keep a small quantity."
The giant, who, being more active than Eradicate, had rather supplanted the aged colored man, did as he was bid, and soon Tom, with Ned and Mr. Damon to help him, was preparing for the test.
They went some distance away from any of the buildings, for, though Tom was only going to use a small quantity of the explosive, he did not just know what the result would be, and he wanted to take no chances.
"I know from personal experience what the two kinds of powder from which I made this sample will do," he said; "but it is like taking two known quantities and getting a third unknown one from them. There is an unequal force be-
