t, and tell me how I can serve you," he replied.

"Very well. At nine o'clock in the evening, on the sixteenth of October,
a lady living in the Rue d'Ulm sent to the stand in the Rue Soufflot for
a cab. Her baggage was placed upon it, and she went away no one knows
where. However, this lady is a relative of my employer, and he so much
wishes to find her that he would willingly give a hundred francs
over and above the amount you owe him, to ascertain the number of the
vehicle. He pretends that you can give him this number if you choose;
and it isn't an impossibility, is it?"

"On the contrary, nothing could be easier," replied the clerk, glad of
an opportunity to explain the ingenious mechanism of the office to an
outsider. "Have you ten minutes to spare?"

"Ten days, if necessary," rejoined Chupin.

"Then you shall see." So saying the clerk rose and went into the
adjoining room, whence a moment later he returned carrying a large green
box. "This contains the October reports sent in every evening by the
branch offices," he remarked in explanation. He next opened the box,
glanced over the documents it contained, and joyfully exclaimed: "Here
we have it. This is the report sent in by the superintendent of the
cab-stand in the Rue Soumot on the 16th October. Here is a list of the
vehicles that arrived or left from a quarter to nine o'clock till a
quarter past nine. Five cabs came in, but we need not trouble ourselves
about them. Three went out bearing the numbers 1781, 3025, and 2140. One
of these three must have taken your employer's relative."

"Then I must question the three drivers."

The clerk shrugged his shoulders. "What is the use of doing that?" he
said, disdainfully. "Ah! you don't understand the way in which we manage
our business! The drivers are artful, but the company isn't a fool. By
expending a hundred and fifty thousand francs on its detective force
every year, it knows what each cab is doing at each hour of the day. I
will now look for the reports sent in respecting these three drivers.
One of the three will give us the desired information."

This time the search was a considerably longer one, and Chupin was
beginning to grow impatient, when the clerk waved a soiled and crumpled
sheet of paper triumphantly in the air, and cried: "What did I tell you?
This is the report concerning the driver of No. 2140. Listen: Friday, at
ten minutes past nine, sent to the Rue d'Ulm---- do you think of that?"

"It'