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picture in addition the likeness of a northern sea, girt with protruding glaciers from which drift off the floating icebergs with their freight of rock and stone. This rocky freight, as the icebergs melt in lower latitudes, is necessarily scattered over the hill tops, the plains, and valleys of the deep sea-bottom. We must picture also, over broad areas, vast sinkings and upheavals of the land, going grandly on through the slow lapse of centuries; the stranding and piling up of icebergs on shoals and coasts ; the southern migration and subsequent retrogression of northern organisms; and the gradual dawn of softening climatic influences, coupled with the shrinking back of glacial forces to within their present limits.
It was thus by observations conducted in northern lands and seas, and in Alpine valleys, that the true nature of our drift phenomena became gradually elucidated. Professor Ramsay, in the attractive essay now before us, has placed in striking parallel--not from the descriptions of others, but from personal observation and researchsome of the glacier valleys of Switzerland, with the romantic Pass of Llanberis and other valleys of North Wales. Commencing with the Swiss valleys, he lays before us a rapid but graphic sketch of the glaciers of the Aar: shewing how incontestible is the fact, that, vast as are these glaciers now, they shrink into insignificance when compared with their extension in former times. The same fact is observ. able, indeed, with regard to almost all the glaciers of these Alpine valleys. On this subject, after mentioning some modern instances of the advance and retreat of glaciers, Professor Ramsay remarks :“But all such historical variations in the magnitude of glaciers are trifling compared with their wonderful extension in pre-historic periods. There is perhaps scarcely a valley in the High Alps in which the traveller, whose eye is educated in glacial phenomena, will not discern symptoms of the former presence of glaciers where none now exist; and in numerons instances, far from requiring to be searched for, these indications force themselves on the attention by signs as strong as if the glacier had disappeared but a short time before the growth of the living vegetation. So startling, indeed, are these revelations that for a time the observer scarcely dares to admit to himself the justness of his conclusions, when he finds in striations, moraines, roches moutonnées, and blocs perchés, unequivocal marks of the former extension of an existing glacier, a long day's march beyond its present termination; and further, that its actual surface of to-day is a thousand feet and more beneath its ancient level.”
With regard to the Aar valley, the glaciers of which are taken as type-forms in relation to this inquiry, our author observes in addition : “Below the lower glacier of the Aar, the stream winds through one of those gravelly flats, so frequent in old glacier valleys, and at its lower end, where this plain narrows towards the Grimsel, a boss of granitic gneiss, well moutonnée, nearly bars the valleys across which the path leads. It is partly covered by striations, well marked on the slope that looks up the valley, telling the observer not only of the previous extension of the glacier thus far, but also that the ice which filled the plain pressed strongly on the higher side of the boss, and was forced upwards till it fairly slid over the rock, the lower part of the ice being quite unchecked by the opposing bar. I mention this especially, because similar phenomena were often pointed out by Buckland in describing the old glaciers of North Wales. On either hand, all the way from the glacier to this point, the mountain sides show the same mammillated contours that mark the rock above the ice, and a little further down the valley, the signs of glacial action become even unusually obtrusive. A large hill rises from the valley on the right, up which the road winds to the Hospice of the Grimsel. On the left is the narrow gorge of the Aar, and on the other side of the hill the sullen lake of the Grimsel half encircles it far above the level of the river. At its outflow the lake is partly dammed up by a little moraine-like débris; but it requires no soundings to tell that the rounded rocks close by, passing under the rubbish, form the chief retaining barrier of the water. On both banks, except when weather-worn, the rocks are ice-worn, and the lake is nearly looped into two by roches moutonnées that project from either bank toward the centre, like Llyn Idwal above Nant Francon, and the lakes of Llanberis, if these were undivided by the alluvial strip below Dolbadarn Tower. At its farther end a long, narrow, high, rounded barrier of solid rock (over which the glacier formerly poured) crosses the valley, damming up the lake in that direction ; and here so great has been the pressure, that I found proof of the ice having been forced into a narrow transverse fissure, which it polished and striated quite out of the direction of its general flow. The lake is a complete rock basin similar to some of the tarns of North
Wales, and such as I only know in regions where glaciers once have been.
“On the hill that rises behind the Hospice, the glacial striations on the rocks gradually circle round to the further end of the lake, following the sweep of the valley ; and it soon becomes apparent that this hill itself, is but a gigantic roche moutonnée, mammilated and striated all over, on which erratic blocks were left by the decrease of the glacier of the Aar after a period in which it rose so high, that it not only filled the hollow of the lake, and pressed upward over the ridgy barrier at its further end, but actually overflowed the entire hill. If from its polished side you survey the opposite ridge of the Aar valley, the vast size of the old glacier becomes still more strongly impressed upon the mind. A great wall of rock rises sharply above the river course, and on its side the striations which cover it, have been deflected upwards, at a low angle, the effect of the intense jamming to which the thick ice was subjected in its downward course, when obstructed by the great roche moutonnée that rises in the middle of the valley between the lake and the mountains on the opposite side of the Aar. Above this wall, the mountain is moutonnée almost to the very summit, where at length the serrated peaks of the highest ridge rise sharply above the ice-worn surfaces. The valley has been filled with ice almost to the very
brim.” After thus discussing in their past and present bearings, the glacial phenomena of these Swiss valleys, our author turns to the valleys of Cænarvonshire that lie around the majestic Snowden, and traces out, in these, step by step, the former existence of immense glaciers, whose dimensions rivalled in grandeur the great ice-rivers of the ancient Alps. He then considers the question of identity of time with respect to the extinct glacial phenomena of Wales and the ancient extension of the Alpine glaciers. “But these things being true, [the former existence, &c., of glaciers in the valleys around Snowden], what relation in time is there between the old glaciers of Switzerland and those of Wales ? The elements from which to attempt a solution of this question are few. First, it may be said that the signs of glaciation in the former extension of still existing Swiss glaciers, are not only identical in all respects with those of the extinct glaciers of Wales, but also that in many an Alpine valley all the ice marks remain, even when no diminished glacier still holds its place amid its uppermost recesses.
These in all respects may be compared to the ancient glaciers of the neighbouring Jura, the Vosges, or of Wales. Again, when we consider that
the great old glaciers of the Oberland apparently opened out on the broad drift-covered territory that extends northward to the Jura, there is another point of resemblance. So similar in general structure and in all its adjuncts is this Drift with that of the north of Europe, that I see no reason whatever to doubt their identity. To add weight to this opinion, I may quote the high authority of Mr. Smith of Jordan Hill, who informed me, that he recollects seeing in the museum at Berne, a neglected collection of Swiss shells, arctic in their grouping, and subfossil, like those of our Newer Pliocene beds; and in the museum at Geneva a similar collection, among which was Mya Udivalensis. Further, it is well known that in the superficial deposits associated with these, the bones of the great hairy elephant (E. primigenius), and other mammalian remains, occur by the Lake of Geneva, at Winterthur, and in other places; and though no one that I know of, has yet attempted to prove the ploughing of drift out of the mouths of Swiss valleys by the older and larger glaciers, yet in every other respect the conditions are so identical, that I am prepared to expect that this also will be proved, and I cannot resist the conclusion that, when glaciers filled the valleys of Wales, it was at that very time (the Newer Pliocene epoch) that the glaciers of Switzerland attained their great original extension.
Further, in spite of the modern fact that far south of the equator, the cold is greater than in equivalent northern latitudes, it is difficult not to speculate on the probable existence of a climate perhaps colder for the whole world, during what is often called the glacial period ; a period when not only the Alps, but all Scandinavia, were full of great rivers of ice descending to the sea ; when the White Mountains of North America also had their glaciers, (as I was informed in 1857, in conversation with Agassiz,) and when the great glaciers of the Himalayah, as described by Dr. Joseph Hooker, descended 5000 feet below their present levels, the older moraines being in one instance only 9000 feet above the sea, whereas the present end of the glacier lies at a height of 14,000 feet.
Another point often occurs to my mind,—what relation have these extinct glaciers to the human period? This is a subject on which we still are in the dark, but considering that in Newer Pliocene bonecaves, flint knives have been found,—there is reason to believe, coeval with elephants, rhinoceroses, and other Mammalia, partly extinct ;and that in France, at Abbeville and Amiens, well formed flint
hatchets of an old type occur in fresh-water and marine strata of socalled Upper Tertiary date ; and also, that a human skull was dug out of the so-called Pliocene volcanic ashes of Auvergne, it is possible, and perhaps even probable, that, long after the Drift was raised above the sea, the eyes of men may have looked upon the glaciers of Wales, when in their latter days, the ice had shrunk far up into the highest recesses of the mountains.”
In calling the attention of our readers to this ably-written essay, we must not forget to mention, that its author has added much to the interest of his descriptions by a number of charming little vignette illustrations, and by a valuable map of the country around Snowden. In the latter, the directions of the rock-striæ, with the moraines and other vestiges of the ancient glaciers of North Wales, are indicated from Professor Ramsay's personal explorations.
E. J. C.
The Family Herald. John Lovell, Montreal. A periodical of a somewhat novel and attractive character has been added to our Canadian Literature under this name, Issued in the form of a Newspaper sheet, and embracing scientific, literary and general news; it partakes in some respects of the united characteristics of Chamber's Journal, and the London Athenæum. A tale or Dovel runs through a series of chapters, in successive numbers; well selected stories, poems, and literary gleanings occupy other of its columns; and a good space is devoted in each number to Reviews. Its news columns are severally set apart to “Canada and the Lower Provinces,” “England,” “Scotland,” "Ireland," and The “ United States." The only thing omitted is party politics ;-and, without any disparagement to the uses and value of our free press, as one of the elements of our social life and freedom, we believe that to many fair and young readers, The Family Herald will be none the less welcome for the omission.
The Editor of this new Canadian periodical is Mr. G. P. Ure, a gentleman long connected with the press; and the character of the earlier numbers of his new serial, show that he is making the best use of his opportunities and experience. When the great influence of the daily press is considered, not on politics only, but in forming the tastes, and training the minds of so large a portion of the community,