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downs right and left, it forms pinnacles, caves, broken angular boulders? Syenite usually does so in our damp climate, from the weathering effect of frost and rain; why has it not done so over the lake? On that part something (giants perhaps) has been scrambling up and down on a very large scale, and so rubbed off every corner which was inclined to come away, till the solid core of the rock was bared. And may not these mysterious giants have had a hand in carrying the stones across the lake 1 . . . Really I am not altogether jesting. Think a while, what agent could possibly have produced either one or both of these effects?
'There is but one; and that, if you have been an Alpine traveller, much more if you have been a chamois-hunter, you have seen many a time (whether you knew it or not) at the very same work.
'Ice! Yes; ice. Hrymin the frost-giant, and no one else. And if you look at the facts, you will see how ice may have done it. Our friend John Jones' report of plains and bogs, and a lake above, makes it quite possible that in the ice-age (glacial epoch, as the big-word-mongers call it), there was above that cliff a great neve or snow-field, such as you have seen often in the Alps at the head of each glacier. Over the face of this cliff, a glacier had crawled down from that neve, polishing the face of the rock in its descent; but the snow, having no large and deep outlet, has not slid down in a sufficient stream to reach the vale below, and form a glacier of the first order, and has therefore stopped short on the other side of the lake, as a glacier of the second order, which ends in an ice-cliff hanging high up on the mountain side, and kept from further progress by daily melting. If you have ever gone up the Mer-de-Glace to the Tacul, you saw a magnificent specimen of the sort on your right hand, just opposite the Tacul, in the Glacier de Tre"laporte, which comes down from the Aiguille de Charmoz.
'This explains our pebble ridge. The stones which the glacier rubbed off the cliff beneath it, it carried forwards slowly but surely, till they saw the light again in the face of the ice-cliff, and dropped out of it under the melting of the summer sun, to form a huge dam across the ravine; till, the "ice-age" past, a more genial climate succeeded, and neve and glacier melted away; but the "moraine" of stones did not, and remain to this day, the dam which keeps up the waters of the lake.
- There is my explanation. If you can find a better, do ) but remember always that it must include an answer to,— How did the stones get across the lake V
RECENT GEOLOGICAL DISCOVERIES.
Preparations for the British Association Meeting at Aberdeen in 1859.
The gentlemen of the hammer and chisel must immediately prepare a Reform Bill, and re-adjust their nomenclature and classification. Both are uncouth and barbarous as well as unscientific. Recent discoveries have unsettled almost every one of the characters and tests of the age of rocks. Old Werner's Transition class, though founded to some extent on facts, has been long ago discarded. But will hardness or crystalline structure, or the absence even of organic remains, hitherto described as the grand features of the primitive class of rocks, now bear to be trusted as essentialia of classification 1 Every summer's ramble multiplies proofs to the contrary. The mere vicinity of a trapvein, squirted from its boiling caldron below, among the most sedimentary strata, has often baked them into hard crystalline masses, and converted mud-banks charged with shells into beautiful granular marble, as may be seen at Strath, in Skye, under the overlying igneous rocks of the Cuchullins. And perhaps the time is not far distant when it may be difficult to find in the crust of the globe any assemblage of rocks in which organisms may not be detected, although heat, for the most part, has nearly obliterated them.1 Again, a little more patient investigation, we expect, will
1 'The hypothesis,' says Sir Roderick Murchison, in his newly-published edition of Siluria, 'that all the earliest sediments have been so blow to the winds many a fine theory as to the gradual development of species, and will most likely show that at no former period was there an ocean replete with shells and worms low in the scale of organization, which had not on its shores a rich vegetation and a fauna abounding in reptiles, and perhaps birds and quadupeds! Thus, when Hugh Miller wrote his Old Red Sandstone, he described it as peculiarly a salt-water fish formation, in which there was scarcely any shells or vegetables, the faint traces of the latter which he had discovered being only markings of fucoids and similar sea-weeds. So far as then known, the Scottish Old Red Sandstone was the produce of a deep shoreless ocean, to which no decayed forests had been brought down by rains and rivers to become future coal-fields, nor on whose margins and lagunes disported the amphibious crocodile or other allied genera, who could leave the impress of their feet or tails on the soft mud or sand. The formation, in short, was considered very low down indeed, and near the base of the platform of rocks in which rest entombed
altered as to have obliterated the traces of any relics of former life which may have been entombed in them, is opposed by examples of enormously thick and often finely levigated deposits beneath the lowest fossiliferous rocks, and in which, if many animal remains had ever existed, more traces of them would be detected.'
'And yet,' as he again observes, 'the fine aggregation and unaltered condition of those sediments have permitted the minutest impressions to be preserved. Thus, not only are the broad wave-marks distinct, but also those smaller ripples which may have been produced by wind, together with apparent rain-prints, as seen upon the muddy surface, and even cracks produced by the action of the sun on a half-dried surface. Again, as a further indication that these are littoral markings, and not the results of deep-sea currents, the minute holes left by the Annelides are most conspicuous on the sheltered sides of the reptiles in each slab.
'Surely, then, if animals of a higher organization had existed in this very ancient period, we should find their relics in this sediment, so admirably adapted for their conservation, as seen in the markings of the little arenicola, accompanied even by the traces of diurnal atmospheric action.'—Siluria, pp. 20-27.- L. M.
the remains of the earliest races of organized creatures. But what have the discoveries of the last six months established? Why, this, that the Old Red Sandstone of the east coast of Scotland is comparatively a modern formation, —much newer, at least, than the grand and lofty masses of the purple and red conglomerate of the western coast, which they so greatly resemble, but upon which Sir Roderick Murchison has now proved that an extensive series of crystalline quartz-rocks, limestones, and micaceous schists repose, all greatly older than Hugh Miller's fish-beds! The discovery a few years ago of a little frog-like, air-breathing reptile in Morayshire (named the Telerpeton Elginense), has been a bone of contention among the savans, because, according to past theories, it was not easy to admit that it could have lived at the date of the deposition of the Old Red Sandstone; and hence very grave doubts were expressed about it, and much anxiety shown to establish that it belonged to the carboniferous strata, or to a New Red Sandstone formation, which, if it did exist in our district, would be most valuable, from the salt and calcareous deposits in which it usually abounds. But within the last month or so, Sir Roderick Murchison, in company with the Rev. G. Gordon of Birnie, made transverse sections of the whole series of Morayshire freestones, from the edges of the micaceous schist in the interior, to the maritime promontories of Burghead and Lossiemouth, which convinced them that the whole red and yellowish sandstones of the province 'are so bound together by mineral characters and fossil remains, that they must all be grouped as Old Red or Devonian! Nay, more than this, the views of the Director-General of the Geological Survey have been confirmed and extended by the further discovery of foot-prints in the Burghead sandstone, not only of a small reptile like the Telerpeton, but of very large creatures, that in their movements made enormous strides, and whose bushy tails