behind him, was reflected clearly in the panes of glass, and he saw the outlines of dark bodies moving with long footsteps over the tiles and along the coping.  They passed swiftly and silently, shaped like immense cats, in an endless procession across the pictured glass, and then appeared to leap down to a lower level where he lost sight of them.  He just caught the soft thudding of their leaps.  Sometimes their shadows fell upon the white wall opposite, and then he could not make out whether they were the shadows of human beings or of cats.  They seemed to change swiftly from one to the other.  The transformation looked horribly real, for they leaped like human beings, yet changed swiftly in the air immediately afterwards, and dropped like animals.

The yard, too, beneath him, was now alive with the creeping movements of dark forms all stealthily drawing towards the porch with the glass doors.  They kept so closely to the wall that he could not determine their actual shape, but when he saw that they passed on to the great congregation that was gathering in the hall, he understood that these were the creatures whose leaping shadows he had first seen reflected in the windowpanes opposite.  They were coming from all parts of the town, reaching the appointed meeting-place across the roofs and tiles, and springing from level to level till they came to the yard.

Then a new sound caught his ear, and he saw that the windows all about him were being softly opened, and that to each window came a face.  A moment later figures began dropping hurriedly down into the yard.  And these figures, as they lowered themselves down from the windows, were human, he saw; but once safely in the yard they fell upon all fours and changed in the swiftest possible second into—­cats—­huge, silent cats.  They ran in streams to join the main body in the hall beyond.

So, after all, the rooms in the house had not been empty and unoccupied.

Moreover, what he saw no longer filled him with amazement.  For he remembered it all.  It was familiar.  It had all happened before just so, hundreds of times, and he himself had taken part in it and known the wild madness of it all.  The outline of the old building changed, the yard grew larger, and he seemed to be staring down upon it from a much greater height through smoky vapours.  And, as he looked, half remembering, the old pains of long ago, fierce and sweet, furiously assailed him, and the blood stirred horribly as he heard the Call of the Dance again in his heart and tasted the ancient magic of Ilse whirling by his side.

Suddenly he started back.  A great lithe cat had leaped softly up from the shadows below on to the sill close to his face, and was staring fixedly at him with the eyes of a human.  “Come,” it seemed to say, “come with us to the Dance!  Change as of old!  Transform yourself swiftly and come!” Only too well he understood the creature’s soundless call.