can't catch a man until he has committed his crime, can they?"

"No, I suppose not," said the old man, with another glance at the
elder-tree. He bowed to Muller and turned and walked away.

Muller followed him slowly, very much pleased with this meeting, for
it had given him a new clue. There was no reason to doubt the old
man's story. And if this story was true, then the crime had been
committed before half-past nine of the evening previous. For the
old man - he was evidently the janitor in No.1 - had not heard the
shot.

Muller left the scene of the crime and walked towards the four
houses. Before he reached them he had to pass the garden which
belonged to the house with the mansard roof. Right and left of
this garden were vacant lots, as well as on the opposite side
of the street. Then came to the right and left the four new houses
which stood at the beginning of the quiet lane. Muller passed them,
turned up a cross street and then down again, into the street
running parallel, to the lane, a quiet aristocratic street on
which fronted the house with the mansard roof.

A carriage stood in front of this house, two great trunks piled
up on the box beside the driver. A young girl and an old man in
livery were placing bags and bundles of rugs inside the carriage.
Muller walked slowly toward the carriage. Just as he reached the
open gate of the garden he was obliged to halt, to his own great
satisfaction. For at this moment a group of people came out from
the house, the owners of it evidently, prepared for a journey and
surrounded by their servants.