Dr. Cairn walked to the window, with its old-fashioned leaded panes. A
lamp stood by the bedside, and he had tilted the shade so that it
shone upon the pale face of the patient--Myra Duquesne.

Two days had wrought a dreadful change in her. She lay with closed
eyes, and sunken face upon which ominous shadows played. Her
respiration was imperceptible. The reputation of Dr. Bruce Cairn was a
well deserved one, but this case puzzled him. He knew that Myra
Duquesne was dying before his eyes; he could still see the agonised
face of his son, Robert, who at that moment was waiting, filled with
intolerable suspense, downstairs in Mr. Saunderson's study; but,
withal, he was helpless. He looked out from the rose-entwined casement
across the shrubbery, to where the moonlight glittered among the
trees.

Those were the orchid-houses; and with his back to the bed, Dr. Cairn
stood for long, thoughtfully watching the distant gleams of reflected
light. Craig Fenton and Sir Elwin Groves, with whom he had been
consulting, were but just gone. The nature of Myra Duquesne's illness
had utterly puzzled them, and they had left, mystified.

Downstairs, Robert Cairn was pacing the study, wondering if his reason
would survive this final blow which threatened. He knew, and his
father knew, that a sinister something underlay this strange
illness--an illness which had commenced on the day that Antony Ferrara
had last visited the house.

The evening was insufferably hot; not a breeze stirred in the leaves;
and despite open windows, the air of the room was heavy and lifeless.
A faint perfume, having a sort of sweetness, but which yet was
unutterably revolting, made itself perceptible to the nostrils.
Apparently it had pervaded the house by slow degrees. The occupants
were so used to it that they did not notice it at all.

Dr. Cairn had busied himself that evening in the sick-room, burning
some pungent preparation, to the amazement of the nurse and of the
consultants. Now the biting fumes of his pastilles had all been wafted
out of the window and the faint sweet smell was as noticeable as ever.

Not a sound broke the silence of the house; and when the nurse quietly
opened the door and entered, Dr. Cairn was still standing staring
thoughtfully out of the window in the direction of the orchid-houses.
He turned, and walking back to the bedside, bent over the patient.

Her face was like a white mask; she was quite unconscious; and so far
as he cou