terça-feira, 18 de janeiro de 2011

Snow Banners of the Californian Alps by John Muir


Snow Banners of the Californian Alps by John Muir

The crown of the Sierra, decorated with streaming snow banners, was the most sublime storm phenomenon I ever witnessed in the Alps, far surpassing in plain, downright grandeur all the most imposing effects of clouds, floods, and avalanches.
The snow out of which these banners are formed is heaped most beautifully upon the Alps winter after winter, sometimes to a depth of twenty or thirty feet; but it does not come from the sky in the form of big feathery flakes, such as one sees in calmer and more temperate regions, seldom even in the form of complete crystals. For many of these starry blossoms fall before they are ripe, while most of those that do attain perfect development as six-petaled flowers glint against one another in their fall, and are broken into irregular fragments.
This dry, mealy, fragmentary snow is still farther prepared for the formation of banners by the action of the wind. For instead of at once finding rest, like that which falls into the tranquil depths of the forest zones, it is rolled over and over, beaten against bare, jagged rocks, and swirled in pits and hollows, like sand in the pot-holes of a river, until finally the keen crystal angles of the fragments are worn off, and the whole is reduced to dust.
Wherever strong storm winds find this light, well-ground snow dust in a loose condition, upon exposed slopes where there is a free upward sweep, it is tossed back into the sky, and borne onward from peak to peak in the form of banners or cloud-shaped drifts, according to the velocity of the winds and conformation of the slopes upon which they are deflected.
While thus flying through the dry, frosty air, a small portion makes good its escape, and remains in the sky as vapor, for evaporation never wholly ceases even in the most rigorous weather. But by far the greater part, after being driven into the sky again and again, is at length locked fast in firm, bossy drifts or in the wombs of glaciers, some of it to remain silent and rigid for many years ere it is finally melted into music, and sent a-flowing and singing down the mountain-side to the sea.
Yet notwithstanding the abundance of winter snow dust in the Alps, and the frequency of comparatively high winds, and the length of time that the dust remains loose and fully exposed to their action, the production of well-formed banners is, for causes we shall hereafter see, of quite rare occurrence. Indeed, during five winters spent in the Sierra, I have observed only one display of this kind that seemed in every way perfect. This was in 1873, when the snow-laden Alps were swept lengthwise by a powerful norther. I happened to be wintering in Yosemite Valley at the time, that sublime Sierra stronghold, in which one may witness the creation of those forms of storm grandeur that are termed wonderful, almost every day—storms of sunshine, storms of snow, floods, avalanches, changing waterfalls, changing clouds. Yet even here the grand gala day of the north wind seemed surpassingly glorious.
I was awakened in the early morning by the rocking of my cabin and the beating of pine burs on the roof. Detached torrents and avalanches from the main wind-flood overhead were rushing wildly adown the narrow side cañons and over the rugged edges of the walls with loud-resounding roar, arousing the giant pines to magnificent activity, and making the entire granite valley throb and tremble like an instrument that was being played.
But afar on the lofty Alps the storm was expressing itself in still grander characters, which I was soon to see in all their glory.
I had long been anxious to study some points in the structure of the ice cone that is formed every winter at the foot of the main Yosemite Fall, but the blinding spray by which it is invested had prevented me from making a sufficiently near approach. This morning, however, the entire body of the fall was torn into gauzy strips, and blown horizontally along the face of the cliff, leaving the cone entirely dry. And while making my way to the top of an overlooking ledge to seize so favorable an opportunity of examining the interior structure of the cone, the peaks of the Merced group showed themselves over the shoulder of the South Dome, each waving a resplendent banner against the blue sky, as regular in form and as firm in texture as if woven of fine silk. So perfectly glorious a phenomenon of course overbore all other considerations, and I at once began to force my way out of the valley to some dome or ridge sufficiently lofty to command a general view of the main Alpine summits, feeling assured I should find them bannered still more gloriously. Nor was I in the least disappointed.
The side cañon by which I ascended was choked with snow that had been shot down in avalanches from the shelving walls on either side, rendering the climbing exceedingly difficult. But, inspired by the grand vision atop, the most tedious scrambling brought no fatigue, and in four or five hours I stood beyond the walls, upon a ridge eight thousand feet high.
And there, in bold relief, like a clear painting on the sky, appeared one of the most imposing spectacles the eye of man ever beheld. Alps innumerable, black and jagged, rising sharply into the azure, their bases set in solid white, their sides streaked with snow, like an ocean rock with foam; and from every summit, all free and unconfused, a streaming banner, from two to six thousand feet in length, slender at the point of attachment, then widening gradually as it extended from the peak, until about a thousand or fifteen hundred feet in breadth. The colossal cluster of peaks called “The Crown of the Sierra,” and the majestic ranks marshaled along the axis to the north and south, Mounts Ritter, Lyell, M’Clure, the Matterhorn, with their nameless compeers, each with its own refulgent banner waving with a clearly visible motion in the sun-glow, with not a single lightning-bolt to mar the sublime simplicity of the wind tones, not a single cloud in the sky to mar the simple grandeur of the banners.

The snow banners

And now, reader, come with a clear mind for a few moments and fancy yourself standing on this Yosemite ridge, looking with your own eyes; for I assure you there is nothing to which I can point your attention within the whole range of Alpine phenomena that is more impressively sublime.
You are looking eastward. You notice a strange garish glitter in the air, and the gale drives wildly overhead with a loud tempestuous roar; but you feel not its violence, for you are looking through a calm, sheltered opening in the woods, as through a window. There, in the immediate foreground of your picture, rises a majestic forest of silver-firs, blooming in eternal freshness, their foliage warm yellow-green, and the smooth snow cloth beneath them thick-strewn with their beautiful plumes. Beyond, and extending over all the middle ground, are somber forests of pine interrupted by huge swelling ridges and domes; and just beyond the dark upturned edges of the forest you behold the clustered monarchs of the Alps waving their majestic banners. They are twenty miles away, but you would not wish them nearer, for every feature is distinct, and the whole is seen in its right proportions, like a well-hung picture on a parlor wall.
And now, after thus taking a full general view, mark how sharply the black snowless ribs and buttresses and precipitous summits of each peak are defined, excepting the portions veiled by the banners, and how delicately their sides are streaked with snow where it has come to rest in narrow flutings and gorges. Mark, too, how grandly the banners wave as the wind flood is deflected against their ample folds, and how trimly each is attached to the very summit of its peak, like a streamer at a mast-head. How smooth and silky they are in texture, and how exquisitely their fading fringes are penciled upon the azure! See how close and opaque they are toward the point of attachment, yet so filmy and translucent toward the end, you see the peaks dimly beyond, as if looking through ground glass. Yet again observe how some of the longest belonging to the loftiest summits stream perfectly free all the way across the intervening notches from peak to peak, while others pass and overlap each other. And consider how every particle of this wondrous snow cloth is flashing out jets of light, like a diamond.
These are the chief features of the picture as seen from the forest window, and it would still be a surpassingly glorious one were the whole of the fore and middle grounds, with their domes and forests, obliterated altogether, leaving only the black peaks, the white banners, and the blue sky on which they were painted.
Glancing now at the formation of snow banners in a general way, we find that the main causes of the wondrous perfection of those we have been contemplating were the favorable direction and great force of the wind, the abundance of snow dust, and the peculiar conformation of the peaks. It is essential not only that the wind move with great velocity to supply a sufficiently copious stream of dust, but that it shall come from the north. No perfect snow banner ever streams northward from the peaks of the Californian Alps. Had the gale to-day blown from the south, leaving other conditions unchanged, only a dull, confused, fog-like drift would have been produced; for the snow, instead of being spouted up at the tops of the peaks in a condensed current to be drawn out as streamers, would have been shed off around the sides and piled down into the glacier wombs. The regularity and distinctness of form observed in these banners is one of their most striking characteristics. Any one not possessed of the secret of their formation would naturally be led to guess that when the peaks were laden with loose snow, a sufficiently powerful wind driving over them from any direction would fill the sky with a fog of snow without any organization whatsoever; and this, indeed, is pretty nearly the effect produced by all the winds, excepting those from the north. And the cause of the peculiar action of the north wind is found in the peculiar conformation of all the main summit peaks in which the glacier wombs were laid. In general the north sides are concave, the south sides are convex or irregular; and this difference in form between the two sides was almost wholly produced by the difference in the kind and quantity of glaciation to which they were subjected. The north sides were scooped out by residual shadow glaciers of a form that never existed upon the sun-beaten sides.
It appears, therefore, without discussing the question in extenso, that because the shadows of the Alps stretch northward, the residual glaciers stretched northward; and because the residual glaciers stretched northward, the snow banners stretch southward.

 

John Muir

Born - April 21, 1838, Dunbar, East Lothian, Scotland
Died - December 24, 1914, Los Angeles, California
Occupation - Engineer, botanist, naturalist, author, and early advocate of preservation of U.S. wilderness

From Harper’s Magazine, July 1877
© The Harper’s Magazine Foundation. All rights reserved.

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