It is probable that an hour or more elapsed while he sat there, the strange green light growing brighter every moment, and spreading slowly, in flamboyant fingers, upward towards the zenith. As it grew, the spectral vision of _our_ world became relatively or absolutely fainter. Probably both, for the time must have been about that of our earthly sunset. So far as his vision of our world went, Plattner, by his few steps downhill, had passed through the floor of the class-room, and was now, it seemed, sitting in mid-air in the larger schoolroom downstairs. He saw the boarders distinctly, but much more faintly than he had seen Lidgett. They were preparing their evening tasks, and he noticed with interest that several were cheating with their Euclid riders by means of a crib, a compilation whose existence he had hitherto never suspected. As the time passed, they faded steadily, as steadily as the light of the green dawn increased. Looking down into the valley, he saw that the light had crept far down its rocky sides, and that the profound blackness of the abyss was now broken by a minute green glow, like the light of a glow-worm. And almost immediately the limb of a huge heavenly body of blazing green rose over the basaltic undulations of the distant hills, and the monstrous hill-masses about him came out gaunt and desolate, in green light and deep, ruddy black shadows. He became aware of a vast number of ball-shaped objects drifting as thistledown drifts over the high ground. There were none of these nearer to him than the opposite side of the gorge. The bell below twanged quicker and quicker, with something like impatient insistence, and several lights moved hither and thither. The boys at work at their desks were now almost imperceptibly faint.