man, whose face was familiar, had, I recollected,
asked most distinctly whether I was Doctor Boyd--a fact which showed
that the trap had been prepared. I now saw the reason why she was
unable to describe the man's sham illness, and during the morning,
while at work in the hospital wards, my suspicions became aroused that
there had been some deeper motive in it all than the robbery of my
watch or scarf-pin. Human life had been taken for far less value than
that of my jewellery, I knew; nevertheless, the deliberate shooting at
me while I felt the patient's pulse showed a determination to
assassinate. By good fortune, however, I had escaped, and resolved to
exercise more care in future when answering night calls to unknown
houses.

Sir Bernard did not come to town that day; therefore I was compelled
to spend the afternoon in the severe consulting-room at Harley Street,
busy the whole time. Shortly before six o'clock, utterly worn out, I
strolled round to my rooms to change my coat before going down to the
Savage Club to dine with my friends--for it was Saturday night, and I
seldom missed the genial house-dinner of that most Bohemian of
institutions.

Without ceremony I threw open the door of my sitting-room and entered,
but next instant stood still, for, seated in my chair patiently
awaiting me was the slim, well-dressed figure of Mary Courtenay. Her
widow's weeds became her well; and as she rose with a rustle of silk,
a bright laugh rippled from her lips, and she said:

"I know I'm an unexpected visitor, Doctor, but you'll forgive my
calling in this manner, won't you?"

"Forgive you? Of course," I answered; and with politeness which I
confess was feigned, I invited her to be seated. True to the promise
made to her husband, she had lost no time in coming to see me, but I
was fortunately well aware of the purport of her errand.

"I had no idea you were in London," I said, by way of allowing her to
explain the object of her visit, for, in the light of the knowledge I
had gained on the Nene bank two nights previously, her call was of
considerable interest.

"I'm only up for a couple of days," she answered. "London has not the
charm for me that it used to have," and she sighed heavily, as though
her mind were crowded by bitter memories. Then raising her veil, and
revealing her pale, handsome face, she said bluntly, "The reason of my
call is to talk to you about Ethelwynn."

"Well, what of her?" I asked, looking straig