fence at No. 620 when he detected the first
signs of a stir; these were the low sounds of careful steps on the walk
and the murmur of conversation. He crouched in the shadow thrown by the
house; the steps grew nearer and he recognized the voices as those of
Big Slim and Bohlmier.

"I haf not much strength," wheezed the Swiss. "Holt me up! Ach! what a
grip! It was like a gorilla's!"

As they drew opposite to Bat, he saw in an uncertain sort of way that
the burglar was supporting his friend.

"Grip!" said Big Slim. "Well, the wallop he carried had some heft, too.
Once I thought I had him; he stood right in front of me; but as I was
reaching for my 'gat' he drove one at me that a bull couldn't have stood
up under."

"That woman!" gasped Bohlmier, "she is full of tricks, yet. Who would
haf thought she had somebodies here with her."

What the burglar replied Bat could not catch, for by this time they had
reached the sidewalk. Under the light he saw the Swiss was holding to
the other feebly, and that his steps were tottering and weak.

"I must have shut down on him even harder than I thought," said Bat to
himself. "It was the knife that did it, and him whipping it out on
Nora."

He waited until the two had disappeared; then he made his way softly
around the house on the side he had not examined before. Here the
windows were all blank and dark except one at the extreme rear. There he
could see the colored maid washing some glassware; this window was
partly open and he heard the woman's voice singing:

"Swing low, sweet chariot,
Come fo' to carry me home."

Bat stood for a while in silent inspection of the place.

"Nothing doing, evidently," he said. "Just as quiet as you please."

He turned his eyes for a few moments upon the surrounding houses; and
when they wandered back he noted with a start that one of the upper
windows was now illuminated. He stared steadfastly at it, and as he was
doing so the light grew brighter; he stood wondering at this, then he
saw Mary Burton, a candle in her hand, appear at the window. But this
was only for a moment; she moved away and the light dimmed, finally
disappearing completely.

"She's left the room and closed the door," said Bat.

A few moments passed, and then a second window, this time on the floor
below, flashed up with light. It remained so for some little time, now
growing dimmer, and now stronger, showing that the girl was moving about
the room. Then, like the o