ss to mother and me."

"I haven't done anything," Larry replied. "I am only too glad to be
of service to you. But I may be able to find out something by this
envelope."

"I don't see how."

"Will you let me take it to the sub-station?"

"Of course. But what good will that do?"

"I want to ask the sorters and clerks in charge if they remember
having handled it. I may find the carrier who brought it in from the
box, and he can tell in what locality it was."

"But how can they remember when they must handle thousands of
letters every day?"

"Perhaps they cannot, but it is worth trying. You see in that
section of the city are mostly foreigners, who write a peculiar
hand, and use stationery anything but clean or of this quality. This
envelope and paper are of an expensive kind."

"Yes, they are some father had made to order for his private
correspondence. I did not know he took any to Europe with him, but
he must have."

"It may be that a letter carrier or mail sorter took enough notice
of the envelope to remember it," Larry went on. "Besides there is a
small blot on it, and the way in which the stamp is put on shows
that some glue or paste was applied to the envelope. Probably he
used an old stamp which had no mucilage on. To make it fast to the
envelope your father, or whoever posted the letter, would have had
to use some sticky substance, and, in doing so, he has put it on a
little too thick. Some spread out from under the stamp and soiled
the envelope.

"Of course the sorters and carriers don't pay much attention to the
pieces of mail, except to see that they are properly stamped and
addressed, but it's worth trying. This envelope would attract
attention if anything would."

"And you are going to use that for a clue?"

"I'm going to try. It may be useless. If we can find in what
particular locality it was mailed we can have the police keep a
watch for your father. He may mail other letters there."

"But my father is not a criminal. Why should the police watch for
him so particularly. They are keeping a general lookout now, but I
wouldn't like to think they were lying in wait for him."

"It's the only way to find him," said Larry. "Of course it's
unpleasant, but there is evidently some mystery here, and that's the
best way to clear it up."

"But he says he has to stay away for a while," argued Grace. "Maybe
he wouldn't like to be found."

"Of course that point has to be considered," Larry admitted.