If we, in imagination, looked from the moon upon the earth, we should see the same phases as are now noticed in the moon; and when it is just before new moon on the earth, the earth will appear fully illuminated from the moon. We would also observe (from the moon) that the brightness of the illuminated part of the earth would vary from time to time, according to the changes in the earth's atmosphere. More light would be reflected to the moon from the clouds in our atmosphere than from the bare earth or cloudless sea, since clouds reflect more light than either land or sea. Accordingly, we arrive at this curious fact--that the extra brightness of the _dark_ body of the moon is mainly determined by the amount of _cloud in our atmosphere_. Accordingly, I concluded that there must be clouds to the west, though I could not see them, which reflected rays of light and faintly illuminated the shadowed part of the moon. It had become much colder, and I concluded that during the night the cloud-particles, if driven near by the wind, would condense into rain. And, assuredly, next morning I was gratified to find that rain had fallen in large quantities, substantiating the theory. There is much pleasure in verifying such an interesting problem. The dark body of the moon being more than usually visible is one of our well-known and oldest indications of coming bad weather. And at once came to my memory the lines of Sir Patrick Spens, as he foreboded rain for his crossing the North Sea:-- "I saw the new moon late yestreen Wi' the auld moon in her arm; And if we gang to sea, master, I fear we'll come to harm." This lunar indication, then, has a sound physical basis, showing that near the observer there are vast areas of clouds, which are reflecting light upon the moon at the time, before they condense into rain by the chilling of the air. According to the old Greek poet, Aratus: "If the new moon is ruddy, and you can trace the shadow of the complete circle, a storm is approaching." CHAPTER XVIII AN AUTUMN AFTERGLOW A brilliant afterglow is welcomed for its surpassing beauty and a precursor of fine fixed weather. A glorious sunset has always had a charm for the lover of nature's beauties. The zenith spreads its canopy of sapphire, and not a breath creeps through the rosy air. A magnificent array of clouds of numberless shapes come smartly into view. Some, far off, are voyaging their sun-bright paths in silvery folds; others float in golden groups. Some masses are embroidered with burning crimson; others are like "islands all lovely in an emerald sea." Over the glowing sky are splendid colourings. The flood of rosy light looks as if a great conflagration were below the horizon.