Exchange. This was quite an institution of Bridgeport, and
generally interested railroad men. Clark was very agreeable to the
proposition made by his companion to look over the place. They found a
fine library and a variety of drawings and models, all along railroad
lines.

"This suits me exactly," declared Clark. "I am not and never will be a
practical railroader, but I like its variety just the same. Another
thing, a fellow learns something. Say, look there."

The speaker halted his companion by catching his arm abruptly, as they
turned into a small reading room after admiring a miniature
reproduction in brass of a standard European locomotive.

"Yes, I see," nodded Ralph, with a slight smile on his face, "our
friend, Wheels."

Both boys studied the eccentric youth they had seen for the first time
a few hours previous. He occupied a seat at a desk in a remote corner
of the room. Propped up before him was a big volume full of cuts of
machinery, and he was taking notes from it. A dozen or more smaller
books were piled up on a chair beside him.

Young as he was, there was a profound solemnity and preoccupation in
his methods that suggested that he had a very old head on a juvenile
pair of shoulders. As Ralph and his companion stood regarding the
queer genius, an attendant came up to Wheels. He touched him politely
on the shoulder, and as the lad looked up in a dazed, absorbed way,
pointed to the clock in the room.

"You told me to inform you when it was two o'clock," spoke the
attendant.

"Did I, now?" said Wheels in a lost, distressed sort of a way. "Dear
me, what for, I wonder?" and he passed his hand abstractedly over his
forehead. "Ah, I'll find out."

He proceeded to draw from his pocket the selfsame memorandum he had
consulted in the case of Jim Scroggins. He mumbled over a number of
items, and evidently struck the right one at last, for he murmured
something about "catch the noon mail with a letter to the patent
office," arose, put on his cap, and hurriedly left the place,
blissfully wool-gathering as the fact that noon had come and gone
several hours since.

"I'm curious," observed Clark, and as Wheels left the place he
followed the attendant to the library office, and left Ralph to stroll
about alone, while he engaged the former in conversation. In about
five minutes Clark came back to Ralph with a curious but satisfied
smile on his face.

"Well, I've got his biography," he announced.

"Whose--Wh