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74 CHEMICAL AND SPECIFIC ACTION OF THE LIGHT.

connection of it with the directive power of the mariner's needle. The auroral, or electric lights, strengthen the analogy, and tend to confirm the idea that the atmosphere of these regions receives or acquires some specific powers developed by the action of light. What agent more mysterious, more subtle, more energetic than light in its high chemical action as displayed by photography ? The rapid alterations of temperature in these high latitudes, and the constant action of light and the development of electricity, show that the three agents, or acting forces, are in full operation here, and effect some beneficial influence on a scale of considerable magnitude.

It is a beautiful subject of contemplation, and a source of pleasure, to spread a charm upon realms of darkness and direct the mind to cheerfulness. And what a coincidence of opinion obtains between Milton and Faraday upon the magnetic powers of light! How rapid are the actions of life and decay in the tropics ; how slow is the one and how checked is the other in these regions ! Here are displayed those conservative properties which make them the regions of puritypetrified by cold and encased in ice, chemical action is suspended. And the reeking and pestilential vapours of the earth, borne hence upon the wings of the wind, are spread aloft and condensed by the cold, the vapour

is precipitated, and the gases, in their attenuated form and minute division, are exposed to the purifying influence and decomposing chemical action of almost continuous light, whose actinic beams here prevail in the upper

ACTINISM AND ELECTRIC LIGHT.

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strata of the atmosphere. Here is developed the almost continuous play of the electric light; and is its power less than an electric or galvanic battery, whose intensity may be low, but its action constant ? The polar regions are the ends of the earth's great battery, and where the most important processes are carried on for the benefit of the whole. Light, heat, and electricity, the three elements of nature, display peculiar properties in these regions. And it is well-known that snow-water contains a large amount of oxygen; but, oh, nature ! thy volume is full of benefits and blessings too large for us to

scan.

The summary report of the principal points of the climate and seasons at Melville Island is, in every respect, valuable and important. Inasmuch as the locality is peculiar, being beyond the verge of the habitable world, and from which the sun withdraws his cheering presence for the lengthened period of eightyfour days, and winter assumes its utmost rigour, whichever way the eye is turned it meets a picture calculated to impress upon the mind an idea of inanimate stillness — of that motionless torpor with which

our feelings have nothing congenial; of anything, in short, but life. In the very silence there is a deadness with which a human spectator appears out of keeping. The presence of man seems an intrusion on the dreary solitude of this wintry desert, which even the native animals have for a while forsaken. Water is unknown in its natural state for eight months in the year, and

, all that is used must be procured by artificial heat

76

MELVILLE ISLAND THE COLDEST REGION.

melting the snow or ice. But even when summer comes, and the sun wheels round in one continuous circle for ninety-six days without setting, yet with all this glorious light, how feeble is the heat. The mean temperature of the warmest month is only 42 degrees, presenting us with an example of the coldest known climate. It stands at the bottom of the list, and exhibits to us one of the extremes of the atmosphere, the mean temperature of the year being 2 degrees below zero, and without a recorded parallel. This privation of heat, the zero of the thermometer very significantly expresses, and is, indeed, most appropriate, for vegetation only languishes in its feeblest forms, and, in fact, almost dwindles down to nothing.

And yet, strange to say, these regions once bloomed with verdure, and had a rich and luxuriant vegetation, for the tomb of nature declares the fact, by the abundance of its organic remains, which are but the epitaphs of pre-existing races. True, it is the language of the dead, but it is intelligible enough to the most common observation ; for here are found relics of plants and animals which no longer live in these regions, but are the inhabitants of warm and sunny climes like the tropics of the present day. These now frozen regions supported forests of dicotyledonous trees, as the abundance of fossil wood declares. But the important article of bituminous coal, of the oldest coal formation, is dispersed over several localities of these sterile regions.

If coal is the resulting product, as geologists state, of

GEOLOGICAL EVIDENCES OF CHANGE OF CLIMATE. 77

pre-existing vegetation, how comes this coal intruded here, where a piece of wood is now unknown ? What changes, vast and great, must have taken place in the temperature and climate of these regions ! Captain Parry says,

“ We found innumerable fossils in the limestone, principally shells and madrepore, and on a hill abreast of the Hecla, at an elevation of 400 feet above the level of the sea, shells occurred in great abundance and perfection. Indeed, it was quite astonishing in looking at the numberless fossil animal remains occurring in the stones, to consider the countless myriads of shellfish and marine insects which must once have existed on this shore. The fossil corals of the secondary limestones intimate that before, during, and after, the deposition of the coal formation, the waters of these seas were as warm as those of the equatorial seas, etc.

Whence can these things be, but in the vivifying warmth of the glorious sun-beams? But how can we ever dream of such a state amid these chilling scenes ? Myriads of

ages have long rolled away since such things were ; but what once was, may be so again, and if the course of countless years has banished the sun, and capped these realms with snow and ice, so in ages yet to come, the sun may be ordered back, and shine again in all his glory upon these benighted realms, and clothe them with their wonted verdure, and man, or some being of intelligence, take possession of the land and all its treasures, which are now lodged in nature's storehouse, and are but as jewels in a casket, ready

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RECURRING PERIODS OF COUNTLESS AGES.

to be opened and unfolded by Omnipotence Divine. For what are ten thousand ages, or millions of centuries, in His sight, of whom it is said, that " a thousand years are but as yesterday, seeing that is past as a watch in the night? Thou turnest man to destruction : again thou sayest, Return again, ye children of men !” The nations of the earth pass away, and the very land and country they inhabit may be as tenantless and as cheerless as Melville Island, which, in its turn, may rise up to greet the sun, and smile again with verdure.

Is this a fable, and beyond imagination ?—when geologists even presume to tell us that such was once the state of happy England—that tropic suns have shined for ages, as our coal-fields testify; after that, icebergs and glaciers have capped the land. If such was the case, and Melville Island would seem almost to certify the fact, then England's fate may be again to change its scene to · Melville's present state, and that become the England of its day. For can we think that all the buried treasures of the arctic regions—its gems, its metals, earths, and beds of coal—are all to lay as useless products in the womb of time? Why should we exempt them from the general plan? They wait alone the fiat of Divine Will to call them forth at his own appointed time; and, when he bids the sun revisit them again, these realms will teem with life and joy. Thus, all is over-ruled by climate, which is the essential element of organic life, and as Milton has truly and beautifully said

“The sun is of this great world both soul and eye.”

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