When a long, low wail smote their ears, their hearts leaped into their throats.  They were travelling along the edge of a black ravine.  Halting, they stood with suspended breath, staring down into the darkness.

The cry came again, yet more piercing; then suddenly it split into a hissing sound like a kettle boiling over.  Alwin broke into a nervous laugh.  “Cats!” he said.

But Sigurd stiffened as quickly as he had relaxed.  “One of Skroppa’s!  She swarms with them.  See!  Is not that a light down there?”

A sudden flicker there certainly was,—­if it was not a ghost-fire.  The last cloud scurried from before the face of the long-suffering moon; before the wind could bring up another fleecy flock, the pale light crept down into the hollow and revealed the dark outline of a cabin clinging among the rocks.

Alwin slipped out of his skees and made sure of his knife.  “That, then, is her house.  We will leave the skees here.”

“Though you never were known to heed advice, I will offer you another piece,” Sigurd answered.  “We must go softly; and if we find the door unlocked, enter quickly and without knocking.  Otherwise it is possible that we will stay outside and talk to the stones.”

It was a tedious descent, yet somehow the time seemed plenty short enough before they stood at the threshold.  The stillness at the bottom of the hollow was death-like; only the flickering light on the window spoke of life.  Silently the door yielded to Alwin’s touch.

Darkness and a dying fire were all that met their eyes.  They thought the room empty, and took a step forward.  Instantly the space was alive with the green eyes of countless cats.  The air was split with yowlings and spittings and hissing.  Soft furry bodies bounced against them and bit and clawed around their legs.  From the farthest corner came the lisping voice of a toothless old woman.

“Who dares interrupt my sleep when the visions of things I wish to know are passing before me?  Better would it be for him to put his hand into the mouth of the Fenriswolf.”

Alwin said slowly, “It is the English thrall.”

After a pause, the voice answered crossly, “I know no English thrall.”

“How comes it, then, that more than a year ago you told something concerning him which made Egil Olafsson his mortal foe?”

Out of the darkness came a sudden cackling laugh.  “That is true.  I told the Black One that the maiden he loved would love an English thrall instead.  And he wished to stick his sword through me!”

“Is that what you told him?” cried Alwin, in amazement.

Sigurd echoed the cry.  Yet as their minds ran back over Egil’s strange actions, they could not doubt that this was the key that unlocked their mystery.

From an invisible corner came a stir, a creak, and then the sound of feet lighting softly on the floor.  A tiny figure appeared on the edge of the shadows beyond the dying fire.  The light fell upon furry gray feet; and Alwin’s first thought was that a monstrous cat had dropped down.  Then the flames leaped higher, and showed a furry cloak and a furry hood, and from its fuzzy depths protruding, a sharp yellow beak for a nose, and a hairy yellow peak for a chin.  Of eyes, one saw nothing at all.