It was all so confused and confusing, as though the little room he knew had become merged and transformed into the dimensions of quite another chamber, that came to him, with its host of cats and its strange distances, in a sort of vision.

But these changes came about a little later, and at a time when his attention was so concentrated upon the proceedings of Smoke and the collie, that he only observed them, as it were, subconsciously.  And the excitement, the flickering candlelight, the distress he felt for the collie, and the distorting atmosphere of fog were the poorest possible allies to careful observation.

At first he was only aware that the dog was repeating his short dangerous bark from time to time, snapping viciously at the empty air, a foot or so from the ground.  Once, indeed, he sprang upwards and forwards, working furiously with teeth and paws, and with a noise like wolves fighting, but only to dash back the next minute against the wall behind him.  Then, after lying still for a bit, he rose to a crouching position as though to spring again, snarling horribly and making short half-circles with lowered head.  And Smoke all the while meowed piteously by the window as though trying to draw the attack upon himself.

Then it was that the rush of the whole dreadful business seemed to turn aside from the dog and direct itself upon his own person.  The collie had made another spring and fallen back with a crash into the corner, where he made noise enough in his savage rage to waken the dead before he fell to whining and then finally lay still.  And directly afterwards the doctor’s own distress became intolerably acute.  He had made a half movement forward to come to the rescue when a veil that was denser than mere fog seemed to drop down over the scene, draping room, walls, animals and fire in a mist of darkness and folding also about his own mind.  Other forms moved silently across the field of vision, forms that he recognised from previous experiments, and welcomed not.  Unholy thoughts began to crowd into his brain, sinister suggestions of evil presented themselves seductively.  Ice seemed to settle about his heart, and his mind trembled.  He began to lose memory—­memory of his identity, of where he was, of what he ought to do.  The very foundations of his strength were shaken.  His will seemed paralysed.

And it was then that the room filled with this horde of cats, all dark as the night, all silent, all with lamping eyes of green fire.  The dimensions of the place altered and shifted.  He was in a much larger space.  The whining of the dog sounded far away, and all about him the cats flew busily to and fro, silently playing their tearing, rushing game of evil, weaving the pattern of their dark purpose upon the floor.  He strove hard to collect himself and remember the words of power he had made use of before in similar dread positions where his dangerous practice had sometimes led; but he could recall nothing consecutively; a mist lay over his mind and memory; he felt dazed and his forces scattered.  The deeps within were too troubled for healing power to come out of them.