We now know that our sun, with his attendant planets and satellites, performs a vast circle, embracing perhaps hundreds of thousands of years, round another star, and that we are constantly entering new regions of space untravelled by our earth before. We come from the unknown, and plunge into the unknown; but so much is certain, that our solar system rolls at present through a space but thinly peopled with stars, and there is no reason to doubt that it may once have wandered through one of those celestial provinces where, as the telescope shows us, constellations are far more densely clustered. But, as every star is a blazing sun, the greater or lesser number of these heavenly bodies must evidently have a proportionate influence upon the temperature of space; and thus we may suppose that during the miocene period our earth, being at that time in a _populous_ sidereal region, enjoyed the benefit of a higher temperature, which clothed even its poles with verdure. In the course of ages the sun conducted his herd of planets into more solitary and colder regions, which caused the warm miocene times to be followed by the glacial period, during which the Swiss flat lands bore an Arctic character, and finally the sun emerged into a space of an intermediate character, which determines the present condition of the climates of our globe. [Illustration: 12. AURORA SEEN IN NORWAY.] Though Nature generally wears a more stern and forbidding aspect on advancing toward the pole, yet the high latitudes have many beauties of their own. Nothing can exceed the magnificence of an Arctic sunset, clothing the snow-clad mountains and the skies with all the glories of color, or be more serenely beautiful than the clear star-light night, illumined by the brilliant moon, which for days continually circles around the horizon, never setting until she has run her long course of brightness. The uniform whiteness of the landscape and the general transparency of the atmosphere add to the lustre of her beams, which serve the natives to guide their nomadic life, and to lead them to their hunting-grounds. [Illustration: 13. AURORA SEEN IN GREENLAND.]