I took a chair outside the door.  As yet there was no need for me to risk coming again under the subtle influence of last night.  Naturally my thoughts went revolving round the main incidents of the last day and night, and I found myself arriving at strange conclusions, doubts, conjectures; but I did not lose myself, as on last night, in trains of thought.  The sense of the present was ever with me, and I really felt as should a sentry on guard.  Thinking is not a slow process; and when it is earnest the time can pass quickly.  It seemed a very short time indeed till the door, usually left ajar, was pulled open and Dr. Winchester emerged, taking off his respirator as he came.  His act, when he had it off, was demonstrative of his keenness.  He turned up the outside of the wrap and smelled it carefully.

“I am going now,” he said.  “I shall come early in the morning; unless, of course, I am sent for before.  But all seems well tonight.”

The next to appear was Sergeant Daw, who went quietly into the room and took the seat vacated by the Doctor.  I still remained outside; but every few minutes looked into the room.  This was rather a form than a matter of utility, for the room was so dark that coming even from the dimly-lighted corridor it was hard to distinguish anything.

A little before twelve o’clock Miss Trelawny came from her room.  Before coming to her father’s she went into that occupied by Nurse Kennedy.  After a couple of minutes she came out, looking, I thought, a trifle more cheerful.  She had her respirator in her hand, but before putting it on, asked me if anything special had occurred since she had gone to lie down.  I answered in a whisper—­there was no loud talking in the house tonight—­that all was safe, was well.  She then put on her respirator, and I mine; and we entered the room.  The Detective and the Nurse rose up, and we took their places.  Sergeant Daw was the last to go out; he closed the door behind him as we had arranged.

For a while I sat quiet, my heart beating.  The place was grimly dark.  The only light was a faint one from the top of the lamp which threw a white circle on the high ceiling, except the emerald sheen of the shade as the light took its under edges.  Even the light only seemed to emphasize the blackness of the shadows.  These presently began to seem, as on last night, to have a sentience of their own.  I did not myself feel in the least sleepy; and each time I went softly over to look at the patient, which I did about every ten minutes, I could see that Miss Trelawny was keenly alert.  Every quarter of an hour one or other of the policemen looked in through the partly opened door.  Each time both Miss Trelawny and I said through our mufflers, “all right,” and the door was closed again.

As the time wore on, the silence and the darkness seemed to increase.  The circle of light on the ceiling was still there, but it seemed less brilliant than at first.  The green edging of the lamp-shade became like Maori greenstone rather than emerald.  The sounds of the night without the house, and the starlight spreading pale lines along the edges of the window-cases, made the pall of black within more solemn and more mysterious.