eer at the time, for it seemed as if the fellow
was afraid I'd recognize him. But I'd never seen him before, so far
as I know, so he needn't have been alarmed. I brought the letter to
the office, and as I sorted my mail, I noted that the stamp had been
stuck on with plenty of mucilage. I also saw the blot, and, as the
envelope was unlike any I had ever seen before, as far as size and
quality of paper went, the thing was impressed on my mind.

"That's all I know about it," the carrier finished, "but I'm sure
the man who gave me the letter was not the missing millionaire. I've
seen his picture too many times lately to be mistaken."

"Then who could it have been?" asked Larry.

"That's a hard question, young man," said the carrier. "It might
have been any one else. I think it was a person who didn't care
about being seen, and didn't want to attract any attention. I guess
he would have been better satisfied to have dropped the letter in
the box when no one was looking, but seeing me there he came up with
it before he knew what he was doing."

"If the letter was from Mr. Potter, and it wasn't the millionaire
who mailed it, he must have got some one to do it," the chief clerk
of the sub-station suggested, and Larry was forced to adopt this
idea. He inquired as to the location of the box at which the carrier
stood when he received the missive, and asked in what direction the
man came from. Having learned these facts, and deciding he could
gain nothing more by staying longer at the sub-station, Larry
hurried to the _Leader_ office.

"Well, I've gained something," he said to himself. "I've got a good
story, and I have a slender clue to work on. I must write the story
first, however. Then I'll go back and tell Grace what I learned."

The account of the letter and the circumstances under which it was
mailed created a new sensation in the Potter mystery, and, as on
several other occasions, the _Leader_ scored a beat.

As soon as he had finished the story Larry went to see Grace, whom
he found anxiously waiting for him. She asked a score of questions
as to what he had learned, and the reporter told her all about his
trip to the sub-station.

"What are you going to do next?" she inquired.

"I think I'll go over on the East Side and make some inquiries. Your
father may be staying there," answered Larry.

Going downtown in an elevated train, and taking a stroll through
that populous section, known as the "East Side," Larry