And the reason was not far to seek.

For if even the worship of the High God, according to the practice of the most enlightened nations, grounds itself upon blood and sacrifice, what wonder if, in the worship of the lords of Hell, the blood of the innocent is an oblation well pleasing and desirable.

Rooted and ineradicable is the desire in man’s heart to know good and evil—­but particularly evil.  And so now Laurence desired to see the sacrifice laid between the horns of the altar and the image above lean over as if to gloat upon the sweet savour of its burning.

Long and carefully Laurence listened before he ventured forth.  The Chapel of the Innocents was dark and silent.  Only a reflection of the red light which burned in the keep struck through the clerestory upon the great cross which swung above the altar.  This, being dispersed like a halo about the sign of Christ’s redemption, rendered the corner where was placed the door into the secret stairway light enough to enable the youth to insert therein Poitou’s key.  The wards were turned with well-accustomed smoothness.

Carefully shutting the door behind him so that if any one chanced to enter the chapel nothing would be observed, Laurence set his feet upon the steps and began his adventure of supreme peril.

It was a narrow staircase, only wide enough indeed for one to ascend or descend at once.  And the heart of Laurence sank within him at the thought of meeting the dread Lord of Machecoul face to face in its strait, black spirals.

He accomplished the ascent, however, without incident, and, passing through another low arch, found himself at the end of the passage over against the door with the curious burned hieroglyphics imprinted upon it.  There was no light in the corridor, and Laurence eagerly set his hand to the latch.  It opened as before and admitted him at a touch.

The temple-like hall was silent and dim.  Only an occasional thrill as if of an earthquake passed across it, waving the heavy hangings and bringing a hot breath of some strange heady perfume to the nostrils.  Laurence, with a beating heart, ensconced himself in a hidden nook behind the door.  The niche was covered by a curtain and furnished with a grooved slab of marble placed there for some purpose he could not fathom.

Yet it was by no means wholly dark.  A light shone into the Chapel of Evil from the opposite side, and through it he could discern shadows cast upon the floors and striding gigantic across the roof, as unseen personages passed the light which streamed into the dusky temple.

In the gloomiest part of the background, hinted rather than seen, he could make out the vast dark figure dominating the iron altar.

Then Laurence remembered that the chamber of the marshal lay on the other side—­the room with the immense fireplace which he had once entered and from which he had barely escaped with his life.