of the house. He was already familiar with the
premises.

The dog-house--the only recently painted structure in the
neighborhood--stood opposite the kitchen door. It was perhaps three
feet in height and four feet long, with a pointed roof. As a door it
had an open arch, and at one side of this was a staple to which a
chain could be attached. The grass in front of the dog-house was worn
away, leaving the soil packed hard. The detective, arriving at the
dog-house, walked around it, gazing at it closely.

The inductive method had failed--as it always failed for Mr. Gubb--and
he meant now to try following a clue in person, if he could find a
clue to follow. Mr. Gubb dropped to his hands and knees and crept
around the dog-house, seeking a clue hidden in the grass. When he
reached the front of the dog-house he paused.

"Ye look that like a dog I was thinkin' ye'd howl for a bone," said
Mrs. Mullarky suddenly from the kitchen door.

Mr. Gubb turned and eyed her with disapproval.

"The operations of deteckating are strange to the lay mind," he said
haughtily. "Those not understanding them should be seen and not
heard."

"An' hear the man!" cried Mrs. Mullarky. "Does a dog-house drive all
of ye crazy? T' see a human bein' crawlin' around on his four legs an'
callin' it detectin' where a dog is that ain't there! Go awn, if ye
wish! Crawl inside of ut!"

"I'm going to do so," said Mr. Gubb, and he did.

Inside, or as far inside as he could get, Mr. Gubb struck a match and
examined the floor of the house. There was straw on it, but nothing
even remotely suggesting a clue. No dog thief had left a glove there.
Mr. Gubb began to back out, and as he backed his head touched
something softer than a pine board. He craned his long neck and looked
upward. Tacked to the inside of the roof of the house was a long
envelope. Mr. Gubb put up his hand and pulled it loose. Then he backed
into the daylight. He sat on the bare spot before the dog-house and
examined the envelope.

The envelope was sealed, but on the face of it was written:--

To be delivered to Judge Mackinnon, after Waffles has been
returned to his house and home. Waffles will be found in the
old cattle-shed on the Illinois side of the river, north
from the turnpike at the far end of the bridge. H. O'H.

It was a clue! Without stopping to silence the scornful laughter of
Mrs. Mullarky, Philo Gubb jumped to his feet and made for the Illinois
s