idn't speak.'

'He did not speak to the American, sir, but he said to the cabman,
"Drive to the Madeleine as quickly as you can."'

'Describe the man.'

'He was a head shorter than the American, wore a black beard and
moustache rather neatly trimmed, and seemed to be a superior sort of
artisan.'

'You did not take the number of the cab. Should you know the cabman if
you saw him again?'

'Yes, sir, I think so.'

Taking this fellow with me I returned to the now nearly empty auction
room and there gathered all my men about me. Each in his notebook
took down particulars of the cabman and his passenger from the lips of
my incompetent spy; next I dictated a full description of the two
Americans, then scattered my men to the various railway stations of
the lines leading out of Paris, with orders to make inquiries of the
police on duty there, and to arrest one or more of the four persons
described should they be so fortunate as to find any of them.

I now learned how the rogue with the pistols vanished so completely as
he did. My subordinate in the auction room had speedily solved the
mystery. To the left of the main entrance of the auction room was a
door that gave private access to the rear of the premises. As the
attendant in charge confessed when questioned, he had been bribed by
the American earlier in the day to leave this side door open and to
allow the man to escape by the goods entrance. Thus the ruffian did
not appear on the boulevard at all, and so had not been observed by
any of my men.

Taking my futile spy with me I returned to my own office, and sent an
order throughout the city that every cabman who had been in the
Boulevard des Italiens between half-past two and half-past three that
afternoon, should report immediately to me. The examination of these
men proved a very tedious business indeed, but whatever other
countries may say of us, we French are patient, and if the haystack is
searched long enough, the needle will be found. I did not discover the
needle I was looking for, but I came upon one quite as important, if
not more so.

It was nearly ten o'clock at night when a cabman answered my
oft-repeated questions in the affirmative.

'Did you take up a passenger a few minutes past three o'clock on the
Boulevard des Italiens, near the Credit-Lyonnais? Had he a short black
beard? Did he carry a small box in his hand and order you to drive to
the Madeleine?'

The cabman seemed puzzled.

'He wore