used his undoing at last, his official undoing that
is, and compelled his retirement from the force. But his advice is often
sought unofficially by the Department, and to those who know, Muller's
hand can be seen in the unravelling of many a famous case.

The following stories are but a few of the many interesting cases that
have come within the experience of this great detective. But they give
a fair portrayal of Muller's peculiar method of working, his looking on
himself as merely an humble member of the Department, and the comedy
of his acting under "official orders" when the Department is in reality
following out his directions.

THE CASE OF THE POCKET DIARY FOUND IN THE SNOW

CHAPTER ONE. THE DISCOVERY IN THE SNOW

A quiet winter evening had sunk down upon the great city. The clock in
the old clumsy church steeple of the factory district had not yet struck
eight, when the side door of one of the large buildings opened and a man
came out into the silent street.

It was Ludwig Amster, one of the working-men in the factory, starting on
his homeward way. It was not a pleasant road, this street along the
edge of the city. The town showed itself from its most disagreeable
side here, with malodorous factories, rickety tenements, untidy open
stretches and dumping grounds offensive both to eye and nostril.

Even by day the street that Amster took was empty; by night it was
absolutely quiet and dark, as dark as were the thoughts of the solitary
man. He walked along, brooding over his troubles. Scarcely an hour
before he had been discharged from the factory because of his refusal to
submit to the injustice of his foreman.

The yellow light of the few lanterns show nothing but high board
walls and snow drifts, stone heaps, and now and then the remains of a
neglected garden. Here and there a stunted tree or a wild shrub bent
their twigs under the white burden which the winter had laid upon them.
Ludwig Amster, who had walked this street for several years, knew his
path so well that he could take it blindfolded. The darkness did not
worry him, but he walked somewhat more slowly than usual, for he knew
that under the thin covering of fresh-fallen snow there lay the ice of
the night before. He walked carefully, watching for the slippery places.

He had been walking about half an hour, perhaps, when he came to a cross
street. Here he noticed the tracks of a wagon, the trace still quite
fresh, as the slowly falli