row huge before my eyes like some ginn of Eastern lore.
Then a curtain of darkness descended. I experienced a violent blow
upon the forehead (I suppose I had pitched forward), and for the
time resigned my part in the drama of the sacred slipper.

CHAPTER XXV

THE WATCHER IN BANK CHAMBERS

At about five o'clock that afternoon Inspector Bristol, who had
spent several hours in Soho upon the scene of the murder of the
Greek, was walking along Fleet Street, bound for the offices of the
Report. As he passed the court, on the corner of which stands a
branch of the London County and Provincial Bank, his eye was
attracted by a curious phenomenon.

There are reflectors above the bank windows which face the court,
and it appeared to Bristol that there was a hole in one of these,
the furthermost from the corner. A tiny beam of light shone from
the bank window on to the reflector, or from the reflector on to
the window, which circumstance in itself was not curious. But
above the reflector, at an acute angle, this mysterious beam was
seemingly projected upward. Walking a little way up the court he
saw that it shone through, and cast a disc of light upon the
ceiling of an office on the first floor of Bank Chambers above.

It is every detective's business to be observant, and although
many thousands of passersby must have cast their eyes in the same
direction that day, there is small matter for wonder in the fact
that Bristol alone took the trouble to inquire into the mystery--for
his trained eye told him that there was a mystery here.

Possibly he was in that passive frame of mind when the brain is
particularly receptive of trivial impressions; for after a futile
search of the Soho cigar store for anything resembling a clue, he
was quite resigned to the idea of failure in the case of Hassan and
Company. He walked down the court and into the entrance of Bank
Chambers. An Inspection of the board upon the wall showed him that
the first floor apparently was occupied by three firms, two of them
legal, for this is the neighbourhood of the law courts, and the
third a press agency. He stepped up to the first floor. Past the
doors bearing the names of the solicitors and past that belonging
to the press agent he proceeded to a fourth suite of offices.
Here, pinned upon the door frame, appeared a card which bore the
legend--

THE CONGO FIBRE COMPANY

Evidently the Congo Fibre Company had so recently