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? 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

have left trails more distinct than the largest seals or otters could do! A well-known labourer in the English deposits (S. H. Beckles, Esq.), whose discoveries, in the Purbeck and Wealden beds, of the jaw-bones of most gigantic reptilia, have been extensive and most important, has recently examined the sandstone quarries at Burghead and Covesea, where he has discovered the most undoubted foot-prints of both large and small animals; and he has sent an extensive set of specimens to London, to be laid before the Geological Society at its winter meetings. Other foot-marks (each having the impression of three or four claws to it) have lately been seen by Sir Roderick, Mr. Martin of Elgin, and Mr. Gordon, and specimens communicated by Mr. P. Duff; so that, in the language of Sir Roderick Murchison's announcement to the late meeting of the British Association at Leeds, 'the presence of large reptiles, as well as of the little Telerpeton, in this upper member of the Old Red Sandstone, is completely established.'

We have not room enough at present to point out further deductions from these facts, and from the discovery, about three years ago, of Silurian fossils in the Southern Highlands and in Ayrshire. We allude to them only to show that, as in the days of Hutton and Playfair, the granite veins which traverse in all directions the schists of Glen-Tilt were the means of establishing the irruptive and igneous origin of granite, so Scotland again turns out to be the battle-field of our men of science, and that very great things may be expected from the explorations which undoubtedly will be made, in connexion with next meeting of the Association, to be held next autumn at Aberdeen, under the eye of the Prince Consort, and at which Sir Roderick Murchison, we are glad to understand, is to take his place as vice-president in all the sections. He is the senior of the three permanent trustees of the Association, and one of the founders of the body in 1831, of whom, strange to say, only five are now

alive. In Sir David Brewster the science of the south of Scotland will be admirably represented and supported; while Sir Roderick, a Ross-shire man, an alumnus of the Inverness Academy (ay, and one who put shoulder to shoulder with the Highlanders on Corunna's bloody sod), will represent the land north of the Spey.

If we might suggest to those who will take the lead in the arrangements for the Aberdeen meeting, we would say that they ought, in the geological section, to prepare for one excursion to Stonehaven, on the eastern coast, and another to Cromarty and Eathie, the scenes of Hugh Miller's labours, on the north.

In Stonehaven bay, and arising out of the harbour, may be seen large dykes of trap ascending the cliff and overspreading the sandstone strata like the branches of a palmtree, and thence overflowing towards the very curious quartzose conglomerate at Dunnottar Castle. On the other or northern horn of the bay, irruptive or felspar rocks jut up in great masses and promontories, shifting and disturbing the sandstone strata; and immediately beyond, these latter give place to hard crystalline and vertical strata, as to which the Association will have to decide whether they are altered Silurian or true primitive rocks.

At Cromarty, the local authorities, we think, should prepare for a visit from a large body of savans (which our railway and steamers will render easy), by exploring some new sections of the rocks on which Hugh Miller used to work. Many of these, it is well known, are below high-water mark, and are thus often covered by the sea; while almost all the nodules containing fossil-fish have been extracted and carried away. Some excavations in the strike or line of the same rocks should be made inland, the gravel and boulderclay should be removed, a few layers of the sandstone underneath loosened, and a few broad sheets of the rock exposed in situ, and so left for the further examination of visitors,