llow," Jack declared. "I've
seen him some place before."

"And so have I," agreed Frank. "And I have a feeling that it was not
under very favorable circumstances."

Each lad racked his brain for a brief moment; then Jack said:

"Well, I guess it doesn't make any difference. Let's go."

He turned about and took a step forward. Frank was about to do the same,
when a sudden thought flashed into his head.

"Wait a minute," he called. "I think I've got him."

"Who?" demanded Jack.

"Davis!" said Frank quietly. I'll bet a pretty red apple that man is
Davis."

"By Jove!" said Jack. "I wonder--now what would he be doing here?"

"I don't know," replied Frank, "but I feel sure that's who it is. Come
on. Let's go after him. We'll lose him in a minute."

Even as he spoke the man he felt sure was Davis turned a corner. Not
waiting for Jack to agree, Frank hurried after him. Jack followed.

The man ahead was walking rapidly, but the two lads gained on him. After
two blocks' walking they were less than fifty yards in the
rear--slouching along cautiously, with heads lowered, for they did not
wish to be recognized if the man were really Davis.

Once the man turned and gazed at the two figures behind him; then,
apparently satisfied that he was not being followed, he moved on again.

After two more blocks he doubled around a corner. Frank and Jack turned
the corner a moment later, just in time to see Davis mount a short
flight of steps, open a door and enter the house.

Frank and Jack walked by, taking careful note of the number of the
house, however, and without glancing up again, continued down the street
and turned the next corner.

There they halted as of one mind while Frank peeped around the corner,
remarking:

"Don't want him to trick us. I don't think he knew he was being
followed, but you never can tell."

The lads stood there for perhaps ten minutes; then Jack reached a
decision.

"As long as we have come this far," he said, "we may as well finish this
man hunt. We'll go and have a look for him."

"How do you figure we are going to get into the house?" demanded Frank.
"Or do you just plan to ring the bell and ask for 'Mr. Davis'?"

"We'll have to get in some way," returned Jack, "or else admit that we
are wrong."

"I won't admit I'm wrong," declared Frank grimly. "I feel positive the
man is Davis."

"So do I," replied Jack; "else I wouldn't be so keen about getting into
that house. We'll go back and