king of
my thumb' as Macbeth's witch used to remark."

Every day save Sunday the electric locomotive had some kind of try-out.
On a level track Tom was sure of his monster invention's qualities; but
in the hills, at a distance from the Hendrickton terminal, it was
another matter.

The grades were steep; but the road was well ballasted. There was
plenty of power. He saw the Jandel locomotives hurry back and forth
with the local trains and realized that this rival invention was by no
means to be despised.

It was at about this time, too, that Mr. Damon appeared in Hendrickton.
Early one forenoon, when Tom and Ned were preparing to take the
Hercules 0001 out of the yard, and Koku was going to his lodgings to
get a little sleep, Tom's eccentric friend came across the tracks,
waving his cane at Tom.

"Bless my frogs and switch-targets!" he ejaculated, "I've walked a mile
from that station to get here. Where are you going with that big
contraption? How does it work? Does it make all the speed you want, Tom
Swift? Bless my rails and sleepers!'

"We're going about a hundred miles out on the road to a good, stiff
grade," Tom told him, having shaken hands in welcome. "If you want to,
get aboard."

"They haven't blown you up yet, or otherwise wrecked the locomotive,"
remarked Mr. Damon, grinning broadly. "I'll have to write right back to
your father--and to a certain young lady who shows a remarkable
interest in your welfare--that you are all right."

"They should already be sure of that," laughed Tom. "Ned and I have
kept the post-office department and the telegraph company very busy."

"They are waiting for my report," announced Mr. Damon, with confidence.
"And I am waiting for yours. Tell me, Tom: Is the locomotive a success?"

"It's going to be," declared the inventor, with decision.

"Bless my trolley wires!" cried Mr. Damon, "I am glad to hear that.
Then you will surely pull down the extra hundred thousand dollars?"

"I believe I shall fulfill every clause of the contract Mr. Bartholomew
and I signed," said Tom.

"Then it's more than a success!" cried his friend. "You have invented
another marvel, Tom Swift!"

"Marvel or not," rejoined Tom, "I believe that the Hercules
Three-Oughts-One will top anything so far built in the way of electric
locomotives."

"Hurrah!" cried Mr. Damon. "Bless my controller! But your father and
Mary Nestor will be glad to hear that!"

Mr. Damon was quite as much interested in th