frightened glance toward the duke's party, and struck
her horse a blow with her whip that sent it bounding forward at a
furious gallop. We reached the river and were crossing as the duke
entered Cambrai Gate--the north entrance to the city. We would enter by
the gate on the south known as the Somme Gate; Cambrai Gate was nearer
the castle.

The duke, I supposed, would go directly to the castle; where Yolanda
would go I could not guess. From outside the Somme Gate we saw the duke
enter Cambrai, but after we had passed under the arch we could not see
him for a time because of intervening houses. The huge, grim pile of
stone known as Peronne Castle loomed ominously on the opposite side of
the small town. Yolanda veiled herself before passing under the gate and
hastened, though without conspicuous speed, toward the castle.

I afterward learned that there was but one entrance to the castle from
the town. It was known as the Postern, though it had a portcullis and a
drawbridge spanning the moat. To the Postern the duke took his way, as
we could see at intervals by looking down cross streets. Yolanda did not
follow him. She held her course down a narrow street flanked by
overhanging eaves. Looking down this street, I could see that it
terminated abruptly at the castle wall, which rose dark and unbroken
sixty feet above the ground.

At the end of this street a stone footbridge spanned the moat, leading
to a strip of ground perhaps one hundred yards broad and two hundred
long that lay between the moat and the castle wall. At either end of
this strip the moat again turned to the castle. The Cologne River joined
the moat at the north end of this tract of ground and flowed on by the
castle wall to the Somme. In a grove of trees stood a large two-story
house of time-darkened stone, built against the castle wall. One could
not leave the strip of ground save by the stone footbridge, unless by
swimming the moat or scaling the walls.

When we reached the footbridge, Yolanda and Twonette, without a word of
farewell, urged their horses across, and, springing from their saddles,
hurriedly entered the house. Max and I turned our horses' heads, and, as
we were leaving the footbridge, saw the duke's cavalcade enter the
Postern, which was perhaps three hundred yards back and north of the
strip on which stood the House under the Wall.

To reach the Postern in the castle wall from the footbridge one must go
well up into the town and cross