Slattin's man, and, like his master, an ex-officer of New York Police,
my friend, Nayland Smith, on the previous evening had set out in quest
of some obscene den where the man called Shen-Yan--former keeper of an
opium-shop--was now said to be in hiding.

Shen-Yan we knew to be a creature of the Chinese doctor, and only a
most urgent call had prevented me from joining Smith upon this
promising, though hazardous expedition.

At any rate, Fate willing it so, he had gone without me; and
now--although Inspector Weymouth, assisted by a number of C. I. D.
men, was sweeping the district about me--to the time of my departure
nothing whatever had been heard of Smith. The ordeal of waiting
finally had proved too great to be borne. With no definite idea of
what I proposed to do, I had thrown myself into the search, filled
with such dreadful apprehensions as I hope never again to experience.

I did not know the exact situation of the place to which Smith was
gone, for owing to the urgent case which I have mentioned, I had been
absent at the time of his departure; nor could Scotland Yard enlighten
me upon this point. Weymouth was in charge of the case--under Smith's
direction--and since the inspector had left the Yard, early that
morning, he had disappeared as completely as Smith, no report having
been received from him.

As my driver turned into the black mouth of a narrow, ill-lighted
street, and the glare and clamor of the greater thoroughfare died
behind me, I sank into the corner of the cab burdened with such a
sense of desolation as mercifully comes but rarely.