By this time it had become quite dark, and the third engineer, who was still in as vigorous a condition as when he started from the camp, imagined that he perceived overhead through the mist what seemed to be small twinkling lights. Immediately he resumed the ascent, and still holding the clue, climbed a few yards higher up the mountain. And then he stopped and held on to the steep rock with both his hands, while he looked at the great Host of Heaven shining in the black depths of space. The cloud terminated above as abruptly as it began below. He had reached the edge, and the vision came upon him suddenly. When he recovered his speech he called softly to his companions to follow up the clue, for the cloud was passed. They struggled up with difficulty, and then all three stood together in silent wonder at the spectacle before them. They had not the slightest conception of its meaning; what the lights were; whether connected or not with their own abode; what were their distances; were they living beings—for a falling star, which suddenly flashed across the sky, suggested this question. Seen through that exceeding thin air, the splendour of the stars and planets was greater than what we, who have only seen them through a much denser medium, are able to conceive. Conspicuous above them all in beauty and brightness was the earth itself, which, being then in opposition, was at its least distance from the observers. When in that position, the earth presents to the Hesperians a much more brilliant object than their planet does to us. For, though not receiving as great a supply of light from the sun as Hesperos does, this deficiency is far more than balanced by the fact that, when in opposition, the whole of the illuminated face of the earth is visible at Hesperos, while only an exceedingly thin crescent of Hesperos is visible at the earth. Notwithstanding the intense coldness of the air, they stood for a long time contemplating the wondrous illumination. At last they became conscious of a change in the scene. The small lights began to grow dim, while the light diffused around them increased. The upper surface of the sea of cloud which lay stretched out on all sides, a few feet below them, gradually manifested itself as a smooth greyish-coloured plain. Behind them, towards the east, the mountain still sloped steeply up; but, at no great height above their heads, the top was distinctly visible. They resolved to continue the ascent, having first fastened the end of their clue, which was now unnecessary, to a conspicuous projection of rock about a hundred feet above the upper cloud surface.