.

During the run to that city, the brakemen speculated upon the chances of
capturing the miscreants, lamenting the fact that the glory had been
denied them.

Arrived at the city, Bob was taken to a room and closely questioned by
the officers, who were soon convinced of the truth of his story.

"Could you identify them if caught?" he was asked.

"If I could hear them speak, I could recognize the voice of the man who
proposed the plan. I did not get a look at them," replied Bob.

Satisfied with this answer, the officers sent instructions to have the
tracks patrolled from Hastings to the long bridge, to search all trains,
and to arrest any tramps found.

This done, arrangements were made to have other detectives at the bridge
in case the men eluded capture.

The waiting was tedious. But at last, about three in the afternoon, word
was received that four tramps, heavily armed, had been captured about
ten miles from the Mississippi river.

Putting Bob into the cab of an engine, six officers climbed aboard, and
a record run was made to the scene of the arrest.

"You sit where you can watch and hear them talk," whispered a detective
in Bob's ear.

At first the prisoners were silent, but under the taunts of the
officers, their reserve weakened, and they began to rail at the men who
had captured them.

Eagerly, Bob listened, then cried, pointing to the smallest of the four:

"That's the man who said he'd get even. I recognize his voice!"

CHAPTER XVI

FAIRFAX AT LAST

Elated by the capture and identification of the would-be train-robbers,
the officers made much of Bob, praising him for remaining to listen
until he had heard the dastardly plot, and commenting on the good
fortune which had placed him just where the tramps were.

Modestly Bob bore the words of commendation, for his mind was on other
matters, as the question he asked evidenced:

"How long before the train arrives that will take me to Fairfax?"

"I'm afraid it will be several days before you can go, Bob," answered
one of the officers.

"Why?" demanded the boy, disappointment evident in his voice and on his
face.

"Because it will be necessary for you to appear in court in order to
convict the prisoners."

"But I don't see why you need me," protested Bob. "I told what I had
heard and then pointed out the man who said he wanted to get even."

"That's just it, son. You are the only one who overheard the
conversation and can identify