They stood for some minutes on the little, square, pulpit-like landing, at the top of the creaking wooden staircase, which led down the side of the building from office to yard, listening to the faint drip of the water through the sluice-gates; the wail of a child outside the walls, and the pacing step of the woman who hushed it; the distant intermittent roar of the song which reached them through the often opened doors of a public-house.  Presently the night-watchman lumbered out of his sentry-box by the gates, his dim lantern sounding pools of mysterious darkness, which were untouched by the solitary gas-lamp in the street outside, and which the faint moonlight only seemed to intensify.

Oswyn drew in a long breath of the cool, caressing air, momentarily straightening his bent figure.  Then he gave a short laugh, which startled Rainham from the familiar state of half-smiling reverie to which he was always so ready to recur.

“The last time I saw the river like this,” he said—­“the last time I was down here at night, that is—­was when I went with a Malay model of mine to his favourite opium den.”

“You have not repeated the experiment?” asked Rainham absently.

“No; not yet, at any rate.  It made my hand shake so damnably for a week afterwards that I couldn’t paint.  Besides, I doubt if I could find the place again.  I couldn’t get the Malay to come away at all; he is probably there still.”

“Beg your pardon, sir,” said the night-watchman hoarsely, when they reached the bottom of the difficult staircase, “there’s been a young woman here asking for a gentleman of the name of Crichton.  I told her there weren’t no one of that name here, and Mr. Bullen, sir, he saw her, and sent her away.  I thought I had better mention it to you, sir.”

“Crichton?  Crichton?” repeated Rainham indifferently.  “I don’t know anyone of that name.  Some mistake, I suppose, or——­ Well, sailors will be sailors!  Thank you, Andrewes, that will do.  Good-night—­or, rather, we shall be back in half an hour or so.”  He turned to Oswyn, who had been hanging back to avoid any appearance of interest in the conversation, for corroboration.  “You will come back, of course?”

“Rather late, isn’t it?  I think I had better catch some train before midnight, if there is one.”

“Oh, there are plenty of trains,” said Rainham vaguely.  “We can settle that matter later.  I can give you a bed here, you know, or a berth, at any rate.”

As they stepped through the narrow opening in the gate, a dark form sprang forward out of the shadow, and then stopped timidly.

“Oh, Cyril!” cried a woman’s plaintive voice.  “Cyril!  I knew you were here, and they wouldn’t let me——­ Ah, my God! it isn’t Cyril after all...!”

The voice—­and it struck Rainham that it was not the voice of a woman of the sort one would expect to encounter in the streets at that hour—­died away in a broken sob, and the girl fell back a step, almost dropping the child she carried in her arms.