"A fee what?" said I.

"What's the French for a cab, sir?"

"Oh, I see what you mean. No. It's all down-hill for the lady. A carriage makes a noise; then there is the cabman to be left behind to tell all that he knows."

Caudel grunted an assent, and we strode onwards in silence. It was an autumn night, but the air was very soft, and the largest of the luminaries shone with the mellow glory of a summer that was yet rich and beautiful in its decay. From afar, in the direction of the Calais Road, came the dim rumbling noise of a heavy vehicle, like the sound of a diligence in full trot; otherwise the dark and breezeless atmosphere was of an exquisite serenity—too placid indeed to please me; for though the yacht was to be easily towed out of Boulogne harbour, I had no fancy for finding myself becalmed close off the pier-heads when the dawn broke.

The Rue de Maquétra was—is, I may say; I presume it still exists—a long, narrow lane leading to a pretty valley. Something more than half-way up it, on the left-hand side, stands a tall convent wall, the shadow of which, dominated as the heights were by trees on such a motionless midnight as this, plunged the roadway into deepest gloom. The whole length of the lane, to the best of my remembrance, was illuminated by two, at the outside by three, lamps which revealed nothing but their own flames, and so bewildered instead of assisting the eye.

Directly opposite the convent wall stood the old château, darkened and thickened in front by a profusion of shrubbery, with a short length of wall, as I have already said, at both extremities of it. The grounds belonging to the house, as they rose with the hill, were divided from the lane by a thick hedge which terminated at a distance of some two hundred feet.

We came to a stand and listened, staring our hardest with all our eyes. The house was in blackness; the line of the roof ran in a clear sweep of ink against the stars, and not the faintest sound came from it or its grounds, save the delicate tinkling murmur of a fountain playing somewhere amongst the shrubbery in front.

"Where'll be the dawg?" exclaimed Caudel in a hoarse whisper.

"Behind the wall there," I answered, "yonder, where the great square door is. Hark! Did not that sound like the rattle of a chain?"

We listened; then said I: