on you fellows, eh?"

"Yes," said Ralph, "we do hear some pretty extravagant stories."

"I suppose so," assented the youth calling himself Marvin Clark.
"Well, I don't want to intrude, but if there's room for myself and my
credentials, I'd rather keep you company than free pass it in the
parlor coach. There you are."

As the boy spoke of "credentials," he drew an unsealed envelope from
his pocket and handed it to Ralph. The latter received it, noting that
it bore in one corner the monogram of the Great Northern, with
"President's office--official business" printed under it. He withdrew
the enclosure and perused it.

The sheet was a letter head of the Middletown & Western Railroad. It
bore on one line in one handwriting the name "Marvin Clark," and
beneath it the words: "For identification," in another handwriting,
and the flourishing signature below "Nathaniel Clark, President."

In typewriting beneath all this were the words: "Pass on all trains,
Marvin Clark," and below that a date and the name in writing of Mr.
Robert Grant, the President of the Great Northern, unmistakably
genuine. There were few employees on the road who were not familiar
with that signature.

"All right," said Ralph, refolding the sheet, re-inclosing it in the
envelope, and handing it back to the stranger. "I guess that passes
you anywhere on the line."

"You see, I've got a sort of roaming commission," explained young
Clark buoyantly, as he got comfortably seated on the fireman's
cushion. "No particular use at school, and father wants me to learn
railroading. The first step was to run down all the lines and pick up
all the information I could. I've just got to put in two months at
that, and then report to family headquarters my store of practical
knowledge. See here."

Marvin Clark drew a blank from his pocket. Some thirty of its pages he
showed to Ralph were filled with memoranda. Thus: "Aug. 22, cattle
freight, Upton to Dover. O. K. Simpson, Conductor." There followed
like items, all signed, forming a link of evidence that the boy had
been a passenger on all kinds of rolling stock, had visited railroad
shops, switch towers, water stations, in fact had inspected about
every active department of several railroad lines that connected with
the Middletown & Western Railroad.

"That is a pretty pleasant layout, I should say," remarked Ralph.

"Oh, so, so," replied Clark indifferently. "Athletics is my
stronghold. If I ever get money enou