Whatever light was about us was reflected by the westward cliffs. It showed a huge undulating plain, cold and grey, a grey that deepened eastward into the absolute raven darkness of the cliff shadow. Innumerable rounded grey summits, ghostly hummocks, billows of snowy substance, stretching crest beyond crest into the remote obscurity, gave us our first inkling of the distance of the crater wall. These hummocks looked like snow. At the time I thought they were snow. But they were not⁠—they were mounds and masses of frozen air!

So it was at first, and then, sudden, swift, and amazing, came the lunar day.

The sunlight had crept down the cliff, it touched the drifted masses at its base and incontinently came striding with seven-leagued boots towards us. The distant cliff seemed to shift and quiver, and at the touch of the dawn a reek of grey vapour poured upward from the crater floor, whirls and puffs and drifting wraiths of grey, thicker and broader and denser, until at last the whole westward plain was steaming like a wet handkerchief held before the fire, and the westward cliffs were no more than a refracted glare beyond.