[344 APPENDIX.]
 
 

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 trap-vein, 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 as semblage 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

[RECENT GEOLOGICAL DISCOVERIES 345]

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 shore-less 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, to gether 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.

[346 APPENDIX.]
 

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 crystal line 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

[RECENT GEOLOGICAL DISCOVERIES. 347]

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 peri-nanent trustees of the Association, and one of the founders of the body in 1831, of whom, strange to say, only five are now

[348 APPENDIX.]
 
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 alunmus 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 over spreading the sandstone strata like the branches of a palm-tree, 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 pre pare for a visit from a large body of savans (which our rail way 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 boulder-clay 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,

[RECENT GEOLOGICAL DISCOVERIES. 349]

without the natural dip or contents of the beds being at all interfered with.

EXTRACT FROM 'FOOTPRINTS OF THE CREATOR,' P. 199.

IN my little work on the Old Red Sandstone, I have referred to an apparent lignite of the Lower Old Red of Cromarty, which presented, when viewed by the microscope, marks of the internal fibre. The surface, when under the glass, resembled, I said, a bundle of horse-hairs lying stretched in parallel lines; and in this specimen alone, it was added, had I found aught in the Lower Old Red Sandstone approaching to proof of the existence of dry land. About four years ago, I had this lignite put stringently to the question by Mr. Sanderson; and deeply interesting was the result. I must first mention, however, that there cannot rest the shadow of a doubt regarding the place of the organism in the geologic scale. It is unequ vocally a fossil of the Lower Old Red Sandstone. I found it partially embedded, with many other nodules half-disinterred by the sea, in an ichthyolitic deposit, a few hundred yards to the east of the town of Cromarty, which occurs more than four hundred feet over the Great Conglomerate base of the system. A nodule that lay immediately beside it contained a well-preserved specimen of the Coccosteus decipiens; and in the nodule in which the lignite itself is contained the practised eye may detect a scattered group of scales of Diplacanthus, a scarce less characteristic organism of the lower formation. And what, asks the reader, is the character of this ancient vegetable, — the most ancient, by three whole formations, that has presented its internal structure to the microscope? Is it as low in the scale of development as in the geological scale? Does this venerable Adam of the forest appear, like the Adam of the in fidel, as a squalid, ill-formed savage, with a rugged shaggy

[350 APPENDIX.]

nature, which it would require the suggestive necessities of many ages painfully to lick into civilisation? Or does it appear rather like the Adam of the poet and the theologian, independent, in its instantaneously-derived perfection, of all after development, — 

'Adam, the goodliest man of men since born
His sons?'

Is this tissue vascular or cellular, or, like that of some of the cryptogamia, intermediate? Or what, in fine, is the nature and bearing of its mute but emphatic testimony on that doctrine of progressive developmentl of late so strangely resuscitated?

In the first place, then, this ancient fossil is a true wood, — a dicotyledonous or polycotyledonous Gymnosperm, that, like the pines and larches of our existing forests, bore naked seeds, which, in their state of germination, developed either double lobes to shelter the embryo within, or shot out a fringe of verticillated spikes, which performed the same protective functions, and that, as it increased in bulk year after year, received its accessions of growth in outside layers. In the transverse section the cells bear the reticulated appearance which distinguish the coniferæ; the lignite had been exposed in its bed to a considerable degree of pressure; and so the openings somewhat resemble the meshes of a net that has been drawn a little awry; but no general obliteration of their original character has taken place, save in minute patches, where they have been injured by compression or the bituminizing process. All the tubes indicated by the openings are, as in recent coniferæ, of nearly the same size and though, as in many of the more ancient lignites, there are no indications of annual rings, the direction of the medullary rays is distinctly traceable. The longitudinal sections are rather less distinct than the transverse one: in

l This alludes, of course, to the development theory of the Vestiges of the Natural History of Creation.

[RECENT GEOLOGICAL DISCOVERIES. 351]

the section parallel to the radius of the stem or bole the circular disks of the coniferæ were at first not at all detected: and, as since shown by a very fine microscope, they appear simply as double and triple lines of undefined dots, that somewhat resemble the stippled markings of the miniature painter; nor are the openings of the medullary rays fiequent in the tangental section (i.e. that parallel to the bark) ; but nothing can be better defined than the peculiar arrangement of the woody fibre, and the longitudinal form of the cells. Such is the character of this the most ancient of lignites yet found that yields to the microscope the peculiarities of its original structure. We find in it an unfallen Adam, — not a half-developed savage.l

The olive-leaf which the dove brought to Noah established

l On a point of such importance I find it necessary to strengthen my testimony by auxiliary evidence. The following is the judgment, on this ancient petrifaction, of Mr. Nicol of Edinburgh, — confessedly one of our highest living authorities in that division of fossil botany which takes cognizance of the internal structure of lignites, and decides, from their anatomy, their race and family: — 

'EDINBURGH, 19th July 1845.

DEAR SIR,  — I have examined the structure of the fossil-wood which you found in the Old Red Sandstone at Cromarty, and have no hesitation in stating, that the reticulated texture of the transverse sections, though somewhat compressed, clearly indicates a coniferous origin; but as there is not the slightest trace of a disk to be seen in the longitudinal sections parallel to the medullary rays, it is impossible to say whether it belongs to the pine or araucarian division. — I am, etc.

'WILLIAM NICOL.'

It will be seen that Mr. Nicol failed to detect what I now deem the disks of this conifer, — those stippled markings to which I have referred. But even were this portion of the evidence wholly wanting, we would be left in doubt, in consequence, not whether the Old Red lignite formed part of a true gymnospermous tree, but whether that tree is now represented by the pines of Europe and America or by the araucarians of Chili and New Zealand. Were I to risk an opinion in a department not particularly my province, it would be in favour of an araucarian relationship.

[352 APPENDIX.]

at least three important facts, and indicated a few more. It showed most conclusively that there was dry land, that there were olive-trees, and that the climate of the surrounding region, whatever change it might have undergone, was still favourable to the development of vegetable life. And, further, it might be very safely inferred from it, that if olive-trees had survived, other trees and plants must have survived also; and that the dark muddy prominences round which the ebbing currents were fast sweeping to lower levels would soon present, as in antediluvian times, their coverings of cheerful green. The olive-leaf spoke not of merely a partial, but of a general vegetation. Now, the coniferous lignite of the Lower Old Red Sandstone we find charged, like the olive-leaf; with a various and singularly interesting evidence. It is something to know, that in the times of the Coccosteus and Asterolepis there existed dry land, and that that land wore, as at after periods, its soft, gay mantle of green. It is something also to know, that the verdant tint was not owing to a profuse development of mere immaturities of the vegetable kingdom, — crisp, slow-growing lichens, or watery spore-propagated fungi, that shoot up to their full size in a night, — nor even to an abundance of the more highly organized families of the liverworts and the mosses. These may have abounded then as now; though we have not a shadow of evidence that they did. But while we have no proof whatever of their existence, we have conclusive proof that there existed orders and families of a rank far above them. On the dry land of the Lower Old Red Sand stone, on which, according to the theory of Adolphe Bron gniart, nothing higher than a lichen or a moss could have been expected, the ship-carpenter might have hopefully taken axe in hand to explore the woods for some such stately pine as the one described by Milton, —

'Hewn on Norwegian hills, to be the mast
Of some great ammiral.'

[APPENDIX. 353]
 
 

SIR RODERICK MURCHISON ON THE RECENT

GEOLOGICAL DISCOVERIES IN MORAYSHIRE.

____________


AT a meeting of the Geological Society of London, held on the 15th December 1858, Part III. of a paper by Sir Roderick Murchison, on 'The Geological Structure of the North of Scotland,' was read.

Referring to his previous memoir for an account of the triple division of the Old Red Sandstone of Caithness and the Orkney Islands, Sir Roderick showed how the chief member of the group in those tracts diminished in its range southwards into Ross-shire, and how, when traceable through Inverness and Nairn, it was scarcely to be recognised in Morayshire, but re-appeared, with its characteristic ichthy olites, in Banffshire (Dipple, Tynet, and Gamrie). He then prefaced his description of the ascending order of the strata belonging to this group in Morayshire by a sketch of the successive labours of geologists in that district; pointing out how, in 1828, the sandstones and cornstones of this tract had been shown by Professor Sedgwick and himself to constitute, together with the inferior Red Sandstone and conglomerate, one natural geological assemblage; that in 1839 the late Dr. Malcolmson made the important additional discovery of fossil fishes, in conjunction with Lady Gordon Cumming; and also read a valuable memoir on the struc ture of the tract, before the Geological Society, of which, to his the author's regret, an abstract only had been published (Proc. Geol. Soc. vol. iii. p. 141). Sir Roderick revisited the district in the autumn of 1840, and made sections in the environs of Forres and Elgin. Subsequently, Mr. P. Duff of Elgin published a 'Sketch of the Geology of

[354 SIR R. MURC'HISON ON THE]

 
Moray,' with illustrative plates of fossil-fishes, sections, and a geological map, by Mr. John Martin; and afterwards Mr. Alexander Robertson threw much light upon the structure of the district, particularly as regarded deposits younger than those under consideration. All these writers, as well as Sedgwick and himself; had grouped the yellow and whitish-yellow sandstones of Elgin with the Old Red Sandstone; but the discovery in them of the curious small reptile, the Telerpeton Elginense, described by Mantell in 1851 from a specimen in Mr. P. Duff's collection, first occasioned doubts to arise respecting the age of the deposit. Still, the sections by Captain Brickenden, who sent that reptile up to London, proved that it had been found in a sandstone which dipped under 'Cornstone,' and which passed downwards into the Old Red series. Captain Brickenden also sent to London natural impressions of the foot-prints of an apparently reptilian animal in a slab of similar sandstone, from the coast-ridge extending from Burghead to Lossiemouth (Cummingston). Although adhering to his original view respecting the age of the sandstones, Sir R. Murchison could not help having misgivings and doubts, in common with many geologists, on account of the high grade of reptile to which the Telerpeton belonged; and hence he revisited the tract, examining the critical points, in company with his friend the Rev. G. Gordon, to whose zealous labours he owned himself to be greatly indebted. In looking through the collections in the public Museum of Elgin, and of Mr. P. Duff; he was much struck with the appearance of several undescribed fossils, apparently belonging to reptiles, which, by the liberality of their possessors, were, at his request, sent up for inspection to the Museum of Practical Geology. He was also much astonished at the state of preservation of a large bone (ischium) apparently belonging to a reptile, found by Mr. Martin in the same sandstone quarries of Lossiemouth

[RECENT GEOLOGICAL DISCOVERIES. 355]

in which the scales or scutes of the Stagonolepis, described as belonging to a fish by Agassiz, had been found. On visiting these quarries, Mr. G. Gordon and himself fortunately discovered other bones of the same animal; and these, having been compared with the remains in the Elgin collections, have enabled Professor Huxley to decide that, with the exception of the Telerpeton, all these casts, scales, and bones belong to the reptile Stagonolepis Robertsoni. Sir Roderick, having visited the quarries in the coast-ridge, from which slabs with impressions of reptilian foot-marks had long been obtained, induced Mr. G. Gordon to transmit a variety of these, which are now in the Museum of Practical Geology, and of which some were exhibited at the meeting.

After reviewing the whole succession of strata, from the edge of the crystalline rocks in the interior to the bold cliffs on the sea-coast, the author has satisfied himself that the reptile-bearing sandstones must be considered to form the uppermost portion of the Old Red Sandstone, or Devonian group, the following being among the chief reasons for his adherence to this view: — 1. That these sandstones have everywhere the same strike and dip as the inferior red sandstones containing Holoptychii and other Old Red ichthyolites, there being a perfect conformity between the two rocks, and a gradual passage from the one into the other. 2. That the yellow and light colours of the upper band are seen in natural sections to occur and alternate with red and green sandstones, marls, and conglomerates low down in the ichthyolitic series. 3. That whilst the concretionary limestones called 'Cornstones' are seen amidst some of the lowest red and green conglomerates, they re-appear in a younger and broader zone at Elgin, and re-occur above the Telerpeton-stone at Spynie Hill, and above the Stagono-lepis-sandstone of Lossiemouth; thus binding the whole into one natural physical group. 4. That whilst the small patches of so-called 'Wealden' or Oolitic strata,

[356 APPENDIX.]
 

described by Mr. Robertson and others, occurring in this district, are wholly unconformable to, and rest upon, the eroded surfaces of all the rocks under consideration, so it was shown that none of the Oolitic or Liassic rocks of the opposite side of the Moray Firth, or those of Brora, Dunrobin, Eathie, etc., which are charged with Oolitic and Liassic remains, resemble the reptiliferous sandstones and 'Cornstones' of Elgin, or their repetitions in the coast- ridge that extend from Burghead to Lossiemouth. Fully aware of the great difficulty of determining the exact boundary line between the Uppermost Devonian and Lowest Carbonferous strata, and knowing that they pass into each other in many countries, the author stated that no one could dogmatically assert that the reptile-bearing sandstones might not, by future researches, be proved to form the commencement of the younger era.

Sir Roderick concluded by stating that the conversion of the Stagonolepis into a reptile of high organization; though of nondescript characters, DID NOT INTERFERE WITH HIS LONG-CHERISHED OPINION — FOUNDED ON ACKNOWLEDGED FACTS — AS TO THE PROGRESSIVE SUCCESSION OF GREAT CLASSES OF ANIMALS, and that, inasmuch as the earliest trilobite of the invertebrate Lower Silurian era was as wonderfully organized as any living Crustacean, so it did not unsettle his belief to find that the earliest reptiles yet recognised; — the Stagonolepis and Telerpeton, — pertained to a high order of that class.

At the same meeting, papers were read 'On the Stagonolepis Robertsoni of the Elgin Sandstones, and on the Foot-marks in the Sandstones of Cummingston,' by Mr. T. H. Huxley; as well as one 'On Fossil Foot-prints in the Old Red Sandstones at Cummingston,' by S. H. Beckles, Esq.
 
 

 _______________

EDINBURGH: T. CONSTABLE,
PRINTER TO TUE QUEEN, AND TO THE UNIVERSITY.