ither of your companions
is a police-officer."

"I give you my word on that," she answered.

He gave a shrill whistle, on which a street Arab led across a
four-wheeler and opened the door. The man who had addressed us mounted
to the box, while we took our places inside. We had hardly done so
before the driver whipped up his horse, and we plunged away at a
furious pace through the foggy streets.

The situation was a curious one. We were driving to an unknown place,
on an unknown errand. Yet our invitation was either a complete
hoax,--which was an inconceivable hypothesis,--or else we had good
reason to think that important issues might hang upon our journey.
Miss Morstan's demeanor was as resolute and collected as ever. I
endeavored to cheer and amuse her by reminiscences of my adventures in
Afghanistan; but, to tell the truth, I was myself so excited at our
situation and so curious as to our destination that my stories were
slightly involved. To this day she declares that I told her one moving
anecdote as to how a musket looked into my tent at the dead of night,
and how I fired a double-barrelled tiger cub at it. At first I had
some idea as to the direction in which we were driving; but soon, what
with our pace, the fog, and my own limited knowledge of London, I lost
my bearings, and knew nothing, save that we seemed to be going a very
long way. Sherlock Holmes was never at fault, however, and he muttered
the names as the cab rattled through squares and in and out by tortuous
by-streets.

"Rochester Row," said he. "Now Vincent Square. Now we come out on the
Vauxhall Bridge Road. We are making for the Surrey side, apparently.
Yes, I thought so. Now we are on the bridge. You can catch glimpses
of the river."

We did indeed get a fleeting view of a stretch of the Thames with the
lamps shining upon the broad, silent water; but our cab dashed on, and
was soon involved in a labyrinth of streets upon the other side.

"Wordsworth Road," said my companion. "Priory Road. Lark Hall Lane.
Stockwell Place. Robert Street. Cold Harbor Lane. Our quest does not
appear to take us to very fashionable regions."

We had, indeed, reached a questionable and forbidding neighborhood.
Long lines of dull brick houses were only relieved by the coarse glare
and tawdry brilliancy of public houses at the corner. Then came rows
of two-storied villas each with a fronting of miniature garden, and
then again interminable lines