een-sensed Muller had felt so
strongly even in that fleeting glimpse of him, came back again here
in the room which was his own little kingdom and the expression of his
mentality.

"Well, what's the trouble here? Where are the wires?" asked the
detective, after the momentary pause which had followed his entrance
into the room. Franz led him to a spot on the wall hidden by a marquetry
cabinet. "Here's the bell, it rings for several minutes before it
stops."

The light of the candle which the butler held fell upon a portrait
hanging above the cabinet. It was a sketch in water-colours, the
life-sized head of a man who may have been about thirty years old,
perhaps, but who had none of the freshness and vigour of youth. The
scanty hair, the sunken temples, and the faded skin, emphasised the look
of dissipation given by the lines about the sensual mouth and the shifty
eyes.

"Well, say, can't your master find anything better to paint than a face
like that?" Muller asked with a laugh.

"Goodness me! you mustn't say such things!" exclaimed Franz in alarm;
"that's the Madam's brother. He's an officer, I'd have you know. It's
true, he doesn't look like much there, but that's because he's not in
uniform. It makes such a difference."

"Is the lady anything like her brother?" asked the detective
indifferently, bending to examine the wiring.

"Oh, dear, no, not a bit; they're as different as day and night. He's
only her half-brother anyway. She was the daughter of the Colonel's
second wife. Our Madam is the sweetest, gentlest lady you can imagine,
an angel of goodness. But the Lieutenant here has always been a care
to his family, they say. I guess he's quieted down a bit now, for his
father--he's Colonel Leining, retired--made him get exchanged from the
city to a small garrison town. There's nothing much to do in Marburg,
I dare say--well! you are a merry sort, aren't you?" These last words,
spoken in a tone of surprise, were called forth by a sudden sharp
whistle from the detective, a whistle which went off into a few merry
bars.

A sudden whistle like that from Muller's lips was something that made
the Imperial Police Force sit up and take notice, for it meant that
things were happening, and that the happenings were likely to become
exciting. It was a habit he could control only by the severest effort of
the will, an effort which he kept for occasions when it was absolutely
necessary. Here, alone with the harmless old man