at the start, however, I see that something about
the power-feed must be changed."

"What is that?" asked Mary, curiously.

"I have only had rigged here one trolley wire. There must be two
attached alternately to the catenary cable. Such a form of twin
conductor trolley will permit the collection of a heavy current through
the twin contact of the pantagraph with the two trolley wires, and
should assure a sparkless collection of the current at any speed. You
noticed that when I took the sharper curves there was an aerial
exhibition. I want to do away with the fireworks."

The fact that the Hercules 0001 was a going and apparently powerful
draught engine satisfied most of the onlookers that Tom Swift was on
the road to final and overwhelming success. The mechanics, indeed, saw
no reason why the locomotive could not be run right out of the yard on
the freight track and coupled to the first train going West. Of course,
the Hercules 0001 could not be delivered to the Hendrickton & Pas Alos
under its own power.

When the locomotive was run back into the shed and stood once more on
the erection track, Tom confessed to Mary and Ned, while Mr. Damon and
Mr. Swift were looking through the huge cab, that he was not at all
pleased with the action of the machine.

"I have the best equipment of any electric locomotive on the rails
today. I am sure of that," he said. "The Hercules Three-Oughts-One is
not as long as those electric locomotives of the C. M. &. St. P. But
that's all right. I have built mine more compactly and, properly
geared, it should have all the power of either the Baldwin-Westinghouse
or the Jandel locomotive."

"Then, Tom dear, what is wrong?" cried Mary.

"Speed. That is what troubles me. Have I got anything like the speed I
am aiming for?"

"Two miles a minute!" breathed Ned Newton. "Some speed, boy!"

"And must you have such great speed, Tom?" repeated Mary.

"That is in my contract. Not only that, but to be of much use to the H.
& P. A. this locomotive must have such speed--or mighty near it. Of
course, under ordinary conditions, two miles a minute for a locomotive
and train of heavy freights would burn up the track--maybe melt the
flanges and throw everything out of gear."

"Why try for it, then?" demanded Mary.

"It is the power suggested by the possession of such speed that we want
in the Hercules Three-Oughts-One. That two miles a minute is a fiction
of the imagination, cannot be claimed. It i