It was unusually cold for the season, and a fine drizzle filled the air.
Chauvenet struck off at once away from the lake, turned into the
Boulevard Helvétique, thence into the Boulevard Froissart with its colony
of _pensions_. He walked rapidly until he reached a house that was
distinguished from its immediate neighbors only by its unlighted upper
windows. He pulled the bell in the wall, and the door was at once opened
and instantly closed.

Armitage, following at twenty yards on the opposite side of the street,
paused abruptly at the sudden ending of his chase. It was not an hour for
loitering, for the Genevan _gendarmerie_ have rather good eyes, but
Armitage had by no means satisfied his curiosity as to the nature of
Chauvenet's errand. He walked on to make sure he was unobserved, crossed
the street, and again passed the dark, silent house which Chauvenet had
entered. He noted the place carefully; it gave no outward appearance of
being occupied. He assumed, from the general plan of the neighboring
buildings, that there was a courtyard at the rear of the darkened house,
accessible through a narrow passageway at the side. As he studied the
situation he kept moving to avoid observation, and presently, at a moment
when he was quite alone in the street, walked rapidly to the house
Chauvenet had entered.

Gentlemen in search of adventures do well to avoid the continental wall.
Mr. Armitage brushed the glass from the top with his hat. It jingled
softly within under cover of the rain-drip. The plaster had crumbled from
the bricks in spots, giving a foot its opportunity, and Mr. Armitage drew
himself to the top and dropped within. The front door and windows stared
at him blankly, and he committed his fortunes to the bricked passageway.
The rain was now coming down in earnest, and at the rear of the house
water had begun to drip noisily into an iron spout. The electric lights