y?" asked Paul, as he prepared to advance boldly into the dense
darkness.

"Sure! We're going to back you up, old fellow. Say the word!" shrilled
Bobolink, close to the other's shoulder.

"Come on, then!"

The lads had hardly advanced five steps when every one caught the dread
sound that Joe claimed to have heard. And Paul, perhaps because he was
the son of a doctor, somehow guessed its true import sooner than any one
of his chums. He knew it was a groan, and that some human being must be
suffering!

There was a slight crackling sound, which was caused by the sudden
drawing of a match along Paul's trousers. Instantly a tiny flame sprang
into existence; and every eye was strained to discover the cause of the
groan.

As the match burned, and the light grew stronger, the boys discovered
that some one lay upon the floor inside the glass enclosed office, and
close to the desk where Mr. Clausin usually sat. Paul, looking further,
had seen that there was a lamp on the stand, and knowing the need of
some better means of illumination than a succession of matches,
instantly moved forward, and started to remove the chimney of this.

It was still a trifle warm, showing that the light must have been blown
out not more than a couple of minutes previously.

Meanwhile, Joe had thrown himself on the floor beside the prostrate
form, which he had already recognized as that of his father. He was
chafing his hands, and calling out in boyish agony, while Jack and
Bobolink looked on with troubled faces.

Paul saw immediately that either Mr. Clausin must have had a fit while
alone, possibly just after he had blown out the lamp, or else some one
had attacked him. His collar and necktie were disarranged, and there was
a nasty bruise on the side of his head; though this might have come when
he fell to the floor.

"If we had some water we might bring him to," observed Paul, when the
man on the floor groaned again, more dismally than before.

"Back of the safe there is a bucket, with a dipper!" said Joe, eagerly.

Fortunately some water remained in the pail, and Paul was able to fill
the dipper. It was just then he noticed the door of the little safe, and
saw that it was open. This was strange, if the owner of the store had
been about to leave when he was seized. And supposing he had fallen in a
fit, who had put out the lamp?

No sooner had he applied the cold water than it seemed to have a magical
effect on the unconscious man. He g