flourished during the miocene period in a country where now even the willow is compelled to creep along the ground. During the same epoch of the earth's history Spitzbergen was likewise covered with stately forests. The same poplars and the same swamp-cypress (Taxodium dubium) which then flourished in North Greenland have been found in a fossilised state at Bell Sound (76° N.) by the Swedish naturalists, who also discovered a plantain and a linden as high as 78° and 79° in King's Bay-a proof that in those times the climate of Spitzbergen cannot have been colder than that which now reigns in southern Sweden and Norway, eighteen degrees nearer to the line.

We know that at present the fir, the poplar, and the beech grow fifteen degrees further to the north than the plantain --and the miocene period no doubt exhibited the same proportion. Thus the poplars and firs which then grew in Spitzbergen along with plantains and lindens must have ranged as far as the pole itself, supposing that point to be dry land.

In the miocene times the Arctic zone evidently presented a very different aspect from that which it wears at present. Now, during the greater part of the year, an immense glacial desert, which through its floating bergs and drift-ice depresses the temperature of countries situated far to the south, it then consisted of verdant lands covered with luxuriant forests and bathed by an open sea.

What may have been the cause of these amazing changes of climate? The readiest answer seems to be a different distribution of sea and land; but there is no reason to believe that in the miocene times there was less land in the Arctic zone than at present, nor can any possible combination of water and dry land be imagined sufficient to account for the growth of laurels in Greenland or of plantains in Spitzbergen. Dr. Oswald Heer is inclined to seek for an explanation of the phenomenon, not in mere local terrestrial changes, but in a difference of the earth's position in the heavens.

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

CHANGE IN ARCTIC CLIMATE.

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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.

Though Nature generally wears a more stern and forbidding aspect on advancing towards 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 colour; or be more serenely beautiful than the clear starlight 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.

But of all the magnificent spectacles that relieve the monotonous gloom of the Arctic winter, there is none to equal the magical beauty of the Aurora. Night covers the snow-clad earth; the stars glimmer feebly through the haze which so frequently dims their brilliancy in the high latitudes, when suddenly a broad and clear bow of light spans the horizon in the direction where it is traversed by the magnetic meridian. This bow sometimes remains for several

hours, heaving or waving to and fro, before it sends forth streams of light ascending to the zenith. Sometimes these flashes proceed from the bow of light alone; at others they simultaneously shoot forth from many opposite parts of the horizon, and form a vast sea of fire whose brilliant waves are continually changing their position. Finally they all unite in a magnificent crown or cupola of light, with the appearance of which the phenomenon attains its highest degree of splendour. The brilliancy of the streams, which are commonly red at their base, green in the middle, and light yellow towards the zenith, increases, while at the same time they dart with greater vivacity through the skies. The colours are wonderfully transparent, the red approaching to a clear blood-red, the green to a pale emerald tint. On turning from the flaming firmament to the earth, this also is seen to glow with a magical light. The dark sea, black as jet, forms a striking contrast to the white snow plain or the distant ice mountain; all the outlines tremble as if they belonged to the unreal world of dreams. The imposing silence of the night heightens the charms of the magnificent spectacle.

But gradually the crown fades, the bow of light dissolves, the streams become shorter, less frequent, and less vivid; and finally the gloom of winter once more descends upon the northern desert.