several handsful of
gravel up against the glass. At first there was no response, but
presently the window was raised, and Roger's head appeared.

"Is that you, Dave?" asked the senator's son, in a low voice.

"Yes, Roger. Will you slip down and let me in."

"Sure thing. Will the side door do?"

"Yes."

No more was said, and the window was closed. Dave hurried to the door
mentioned, and a moment later Roger opened it, and he entered. Then both
hurried upstairs, making as little noise as possible.

"What kept you so long?" asked the senator's son, while Dave was
undressing.

"I'll tell you and Phil in the morning," was Dave's reply. "I've got a
yarn to spin you will hardly believe." And then he went to bed. But it
was a long time before he was able to drop asleep, and then his dreams
were little short of a nightmare.

It was not until Sunday afternoon that Dave got a chance to tell his two
chums the particulars of what had occurred. They listened with keen
attention to all he said, and the face of each plainly expressed his
amazement.

"That's the worst ever!" was Roger's comment. "What were they going to
do with you, Dave?"

"I don't know."

"I believe it was some deep-laid plot," said Phil. "Your getting away
spoiled it all."

"For them, yes,--but not for me," answered Dave, with something of a
grin. "I don't know what I escaped, but I am mighty glad I got away."

"What about your bicycle?" asked the senator's son. "Aren't you going to
try to get that back?"

"Certainly,--and I am going to interview that Doctor Montgomery,
too,--if I can catch him. But I want you two to go along," answered
Dave.

He was glad to take it easy for the rest of the day. On Monday, after
school, the three boys went to Rockville on bicycles, Dave borrowing a
wheel belonging to Buster. They rode straight to the Dunn house, to
find it locked up tightly. In the yard was Dave's machine, standing
against the tree as he had left it.

"I guess the doctor has come and gone," said Dave, after trying all the
doors. "Most likely he'll make himself scarce for a while."

"Why not interview that fellow Shime?" suggested Phil.

"I will," answered Dave, and taking the extra wheel along, the three
students rode around to the Rockville livery stable and garage. Here
Dave asked the proprietor about Shime.

"He has gone," said the man, sourly. "Day before yesterday he took one
of my best autos for a joy ride. When he came back this morn