seconds, as the locked wheels slid toward the end of the
siding, were about as hard to bear as any experience the young inventor
had ever gone through. It was not so much the peril of the accident, it
was the possibility of what might happen to the locomotive.

Within those few moments, however, Tom considered more than the safety
of his companions and himself, and more than the peril of wreck to his
locomotive. He considered the schedule of the trains on this division
of the Hendrickton & Pas Alos and remembered all those that might be
within this sector at this time.

If the locomotive smashed into the bumper with force enough to wreck
the structure, would some approaching train on the westbound track not
be endangered?

The thought was parent to Tom's act before the collision occurred. With
a single swift motion he reached for the signaling apparatus which he
had established in connection with his wireless telephone.

Just the moment before the head of the locomotive rammed that seemingly
immovable barrier at the end of the siding there flashed into the air
from Tom's annunciator the code word agreed upon announcing a wreck,
and the number of the sector on which the electric locomotive was then
running.

The next moment the crash occurred.

Tom had leaped up with a shout of warning. "Hang on!" was his cry. But
when the locomotive had struck and rebounded Ned, from far down the
aisle of the locomotive, wanted to know in a very peevish tone what he
should have hung on to?

"My elbows!" he groaned. "I've skinned 'em, and my back has got a twist
in it like the Irishman thought he had when he put on his overalls
hind-side to. What's happened?"

"Bless my radiolite!" growled Mr. Damon. "My watch crystal is broken
all to finders, if you want to know. Bless my shock-absorbers! you
won't do this locomotive a bit of good, Tom Swift, if you stop it so
abruptly."

"And that's the surest word you ever said," responded Tom, hurrying to
the door. "I don't know what's broken, but we're still on the rails.
The most immediate thing to learn, is the where-abouts of the fellow
who did this."

"Who opened the switch?" cried Ned.

"I believe it was Andy O'Malley. Come on, Ned! Koku is after him and I
don't want him to tear O'Malley apart before I get there."

"O'Malley has got powerful interests behind him, and it might go hard
with Koku if he injured the spy and some of these Westerners caught
him," suggested Mr. Damon.