nd almost every
mechanical establishment in the city where the instrument could have been
used, was subjected to the same inspection, but without discovering
anything. A list of the missing property, and the marks by which it
could be identified, was given to the public and telegraphed all over the
Union. Captain Jourdan declared that it was well to have as many people
as possible looking for these articles. Every known or suspected
criminal in the city was waited on by the police, and required to give an
account of himself on the night of the murder, and it is said that there
was a general exodus of the professional thieves from New York. The ten
days immediately succeeding the murder were singularly free from crime,
so close was the espionage exercised over the criminals by the police.

It is safe to assert that the police never made such exertions in all
their history, to secure a criminal, as in this case. Every sensible
suggestion was acted upon, no matter by whom tendered. Neither labor nor
expense was spared, and all with the same result. Captain Jourdan
literally sank under his extraordinary exertions, his death, which
occurred on the 10th of October, 1870, being the result of his severe and
exhausting labors in this case. His successor, Superintendent Kelso, has
been equally energetic, but thus far--nearly two years after the
commission of the deed--no more is known concerning it than was presented
to Jourdan and Kelso as they stood in the chamber of death, and nothing
has occurred to destroy or shake their original theory respecting the
murderer and his mode of committing the deed. The mystery which
enshrouded it on that sad July morning still hangs over it unbroken.

II. PRIVATE DETECTIVES.

The Detectives, whose ways we have been considering, are sworn officers
of the law, and it is their prime duty to secure the arrest and
imprisonment of offenders. There is another class of men in the city who
are sometimes confounded with the regular force, but who really make it
their business to screen criminals from punishment. These men are called
Private Detectives. Their task consists in tracing and recovering stolen
property, watching suspected persons when hired to do so, and
manufacturing such evidence in suits and private cases as they may be
employed to furnish.

There are several "Private Detective Agencies" in the city, all of which
are conducted on very much the same principles and plan