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Cuvier and Professor Buckland, inconsistent with the Testimony of Moses and the Phenomena of Nature." A general description of the superficial accumulations has been given by Mr Milne-Home in a valuable memoir "On the Lothian CoalFields." This author states, that it is possible to identify and individualise at least seven formations, each having separate characters, and probably belonging to different epochs. Under the existing soil supporting vegetation, there is, 1st, An upper covering of gravel and boulders; 2d, A deposit of sand and shells; 3d, Beds of fine sand; 4th, Beds of fine clay; 5th, Coarse gravel or stony clay; 6th, Lowest boulder-clay; 7th, Beds of sand and gravel. In the "Lithology of Edinburgh," Dr Fleming divides the strata belonging to the modern epoch into three groups,-First, The Taragmite series, formed subsequently to the dressings and groovings of the solid rocks, and, where present, reposing on them. They seem to have been formed when violent aqueous movements were taking place, and probably at a period when the state of our island was widely different from the present. The second, or Akumite series, is chiefly characterised by its laminated clays and sands, and indicates the assorting power of water under circumstances of comparative tranquillity. The third, or Phanerite group consists of deposits produced by causes in ordinary operation, and respecting the circumstances under which they have been formed little obscurity prevails. I had repeated opportunities of visiting the critical sections in this neighbourhood with the late Professor Fleming, and of verifying the accuracy of his observations. I shall therefore make use of these generalised expressions in the remarks which follow.

The lowest bed of the Taragmite group which has been observed in this neighbourhood consists of loose angular fragments of rock, 2 to 3 feet thick, which rest on the edges of strata composed apparently of the same materials, and in other places. of sand and gravel. The extent of this basement deposit is at present but little known. The result of three borings, shown in a diagram which is copied from one in possession of Mr George Robertson, civil engineer, proves that the basement. bed of the Taragmite series is of considerable extent in the neighbourhood of Leith. Two of the borings were made for

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the purpose of Artesian wells, and one for the foundation of a splendid work of art, the new Graving Dock. At a flour-mill situated near the west end of Leith Docks, the section passes through 80 feet of boulder-clay, then through a bed of sand 22 feet thick, resting on the solid rocks. The excavation made for the Graving Dock passed through 24 feet of marine sand; and the boring shows that the boulder-clay is here 35 feet thick, when a bed of sand is again reached 18 feet in thickness, or 4 feet less than at the flour-mill section. At the rope-walk on the north side of Leith Links, the boring passes through a bed of marine sand 30 feet thick, then through 70 feet of boulder-clay, which at this place is found to rest on the mineralised strata, without any intervening bed of sand. Mr Milne-Home, in his "Memoir on the Lothian Coal-Fields," says, "that at Leith, and in the manufactory lately occupied by a Mr Burstall, a well was sunk through the boulder-clay 45 feet. A bed of sand and fine gravel was then reached, from which water immediately gushed up, showing that the bed was probably of considerable extent." I am informed that the boring referred to by Mr Milne-Home was made in King Street, a little to the eastward of South Leith Poorhouse; and the borings since then instituted confirm his remark, and prove that this deposit underlying the boulder-clay is of considerable extent in the neighbourhood of Leith. This lower stratum of sand and shivers possesses a peculiar interest, inasmuch as it seems to imply that a period of time elapsed between the dressings of the rocks and their covering by boulder clay, sufficient to admit of disintegration and the formation of extensive sedimentary deposition. Additional observations on this basement bed of the Taragmite series, and its existence in other localities, are still wanted, and may assist in throwing some light on certain obscure phenomena connected with the formation of the boulder-clay-a deposit which, Dr Fleming remarks, "has been to many pons asinorum." There are numerous examples where the boulder-clay is observed passing upwards into stratified beds of sand and gravel. In the foundation for the new Post-Office of Edinburgh, Mr A. Bryson and myself noticed the upper portion of the boulderclay becoming of a light-brown colour, with an increased pro

portion of sand, and several horizontal layers of sand and gravel distinctly stratified, one of which, at 6 feet below the surface of the clay, was 16 inches thick, and could be traced for 20 feet.

The Akumite group in the ascending order of the superficial strata consists of three distinct kinds of deposits-silt, sand, and gravel. Sections occur in this neighbourhood to prove that, subsequent to the deposition of the Taragmite series, and previous to the commencement of the Akumite group, extensive denudation had taken place, by which the newer or upper portion of the Taragmite beds had been removed. In all the sections examined in this neighbourhood, the silt appears as the basement bed of the Akumite series, and, where present, is seen to rest immediately on the boulderclay. There is evidence to show that in all probability the Akumite group may be regarded as a lacustrine formation, into which marine remains have occasionally been thrown by irruptions of the sea. Like the Taragmite formation, in passing upwards it graduates into sand and gravel; and where sand occurs without the boulder-clay or silt being exposed, its true relation cannot be satisfactorily determined. There are grounds for supposing that deposits of sand belonging to the boulder-clay and silt periods have been frequently confounded with a bed of marine sand of a different origin, to which the name of raised sea-beach bed has been given. This bed belongs to the third group in the ascending scale, or Phanerite series, of the superficial accumulations; and although, as its name implies, it presents characters very distinct and easily observed, it has nevertheless formed the subject of much geological controversy.

At the concluding meeting of the Royal Physical Society for 1859, I gave a brief description of that portion of the socalled raised sea-beach bed which extends between the old sandstone quarry at Granton and the Magdalen Burn, near Fisherrow. I then stated that the lateral extent of this socalled raised sea-beach bed, and its relation to other accumulations of a similar lithological structure, but destitute of any trace of marine remains, had not yet been satisfactorily determined. The importance of this investigation will be readily

admitted when it is considered that it forms, as it were, the starting point whence the great generalisations of geology begin. The raised sea-beach bed is described by Hutton, and is alluded to by his eloquent disciple Playfair, in his “Illustrations of the Huttonian Theory," p. 441. "The marks of an ancient sea-beach," he says, "are to be seen beyond the present limits of the tide, and beds of sea shells, not mineralised, are found in the loose earth or soil, sometimes as high as 30 feet above the present level of the sea. The ground on which the Botanic Garden of Edinburgh is situated (the Old Botanic Garden in Leith Walk), after a thin covering of soil is removed, consists entirely of sea sand, very regularly stratified with layers of a black carbonaceous matter, in thin lamellæ, interposed between them. Shells, I believe, are but rarely found in it, but it has every other appearance of a sea beach." In the "Lithology of Edinburgh," Dr Fleming, in reference to the remarks of Playfair, says,-" The assumption here of sea sand' and 'sea beach' seem alike unwarrantable from the description given of the sand; and I may add," he says, "that the occurrence of sea shells in the sand has not been since authenticated." On the high ground that extends between Granton and North Leith, thence inland towards Edinburgh, I have had opportunities of examining numerous excavations and sections where deposits of sand and gravel are frequently exposed, without finding a trace of marine remains. These deposits constitute the upper portion of the Taragmite and Akumite series, and are extensively distributed over the surface in the vicinity of Leith and Edinburgh. The ground chosen for the various cemeteries, and for the Experimental and Botanical Gardens, is a portion of the same deposit; and the general inequality of the surface seems to indicate that the materials were assorted under the action of strong currents and eddies, in comparatively shallow water. A little to the westward of Leith Fort, there is an interesting section of the boulder-clay, known as the Man-trap, where a bed of ferruginous sand is seen resting on the clay, 15 feet above the high-water line. A short time since a cutting was made for a drain in the sloping bank, which extended from the margin of the cliff up to Anchorfield

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Buildings. The cutting passed through 2 feet of soil, and from 2 to 4 feet of ferruginous sand, in which no marine remains could be detected. The extent of the drain, from the margin of the cliff (which is here vertical) up to Anchorfield Buildings, was 90 feet, with a rise of 5 feet. several years past the sea has been making rapid encroachments upon this part of the coast; and there is evidence to show that, during the last forty years, 90 feet of cliff with a similar gradient has crumbled down and been removed. The bed of sand, which rests on the boulder-clay at a height of 12 to 15 feet above high-water mark, has been considered a portion of the so-called raised sea-beach bed. It would then have been 5 feet lower than at present, and, if the slope continued at the same gradient seaward, would come in contact with the ripple-zone, composed of materials similar to what is now observed at the base of the cliff. This zone extends between the limits of the high-water marks of spring and neap tides, where sands and gravel are thrown up in ridges of ever-varying elevation, and amongst which marine rejectamenta of the most varied character are to be found. The nature and contents of the present ripple-zone deposits are similar to those composing the so-called raised sea-beach bed; and it is difficult to conceive they could have had a different origin. An attentive examination of the heterogeneous contents included in the older deposits, as exposed, for example, at the Foul Burn between Leith and Portobello, will not fail to satisfy the zoologist that the remains of molluscan life, huddled together in a bed several feet thick, could never have been associated during life. The bed is seen resting on the boulder-clay at the level of ordinary spring-tides; and at one spot is even interrupted by a slight rise in the clay of only 3 or 4 feet above the level of the tide. At this place the sea is observed to be again encroaching on the older deposits; and from observations made by my friend Mr William Young of Fillyside, it appears that 10 or 12 feet of the low cliff has fallen down during the last twelve months. Three years ago, a great abundance of living oysters were cast ashore. from the oyster-bed that lies off at a short distance in one or two fathoms water. Several of our geological writers have

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