The usual mode of accounting for the bone-breccias so eommonly found in caverns open to the day can scarcely be considered by any body as quite satisfactory. It seems usually taken for granted that that mixture of sand, clay, small stones, and fragments of bone must necessarily have been brought there by streams of water, or washed in by waves. And yet in many instances—perhaps in by far the great majority of instances—nothing can be imagined as much less likely to have happened than the aggregation of such materials by any means of that kind: that it should have been an occurrence of almost universal prevalence may well be deemed impossible. For under what circumstance can it be conceived that floods of water, in every region where open caverns exist in the rocks, should have picked up a heterogeneous collection of bones just in time to lay them quietly down again in every hole into which the muddy stream could gain access? For we must really suppose so well-timed an acquisition of future fossils, before we can admit the usually received hypothesis of the manner in which they were deposited where we find them; since no one can suppose that the whole of the solid matter borne along by any great flood—not to say by every such flood—could have been such as we observe so constantly in these bone-breccias.

There is less to be said about the animals found fossil in the coal than about the plants. And for this reason, that the vegetables formed the coal; the shells and crustaceous creatures, and fish, and reptiles, were but visitors: or if they lived upon the spot, bore no larger proportion to the stately jungle that sheltered them, than the denizens of our own forests now-a-days do to the trees and undergrowth which give them food and habitation.

Still, animals are far from rare; and the common ones are chiefly bivalve shells and worms. The truly land animals are but few. A rare insect or two has been found in our own country. Dr. Mantell discovered the wing of a fly not unlike the dragon-fly, and supposed to belong to the American genus Corydalis. This insect is figured in Sir R. I. Murchison's Siluria, and is now in the British Museum. And one or two beetles, or rather what have been supposed to be beetles, have been found in Coalbrooke Dale. Cockroaches and crickets have left their wings in tolerable plenty in the coal-shales of Saxony. No doubt they were welcome there amid the coal-solitudes, and put a little life into them. They are far from welcome now. I recommend all who may live in the neighbourhood of the coals to give a little time to hunting for the relics of these old insects, &c.

Old bones, that would be worthless to anybody else, become valuable to the geologist. There may be nothing picturesque or strikingly singular in their appearance. They may be too rotten or too fragile for the manufacturer; too sapless for the agriculturist; nay, too few or too far between to be of any commercial value at all. And yet bits of bones may be inscriptions of much value to the palæontologist. As every letter in the few lines incised on the famous Rosetta stone was a key to some passage in a forgotten language of the past, so every new bit of bone may be the key to some passage in that greater history of a greater past which geology unrolls. Many years ago—how time flies past—I met with a little patch of mammaliferous drift at Folkestone; I gathered every fragment of bone, every tooth, every shell, which the workmen's picks and spades exhumed, and most of what I could not determine myself at that time, Professor Owen, and my then living and active friend, Mr. Turner, looked over and named.

Amongst the bones I then collected were two of form to me before unknown, and which I often since brought back to mind. Two—both fragments of horns—flat at the basal part, perfectly round towards the tip; no goat, nor antelope, nor deer, that I knew, had horns like them; and so those fragments were laid aside (not carelessly) for future thought and comparison. Shortly since in walking through the gallery of the British Museum, I visited the cases containing deers' remains, and there, at once I saw, not the counterparts, but what seemed to me the fac-similes of my bits of horns.

“Not many years ago,” Mr. Salter tells us in his admirable “Lecture on Coal,” printed in this volume, “the ‘bigwigs’ in England were assembled in conclave, and the élite of science was called before them” to determine what certain “lumps of a blackish brown substance” were. Was it carbon? Was it shale? Was it cannel? Was it COAL? Now it was on Friday, the 29th July, 1853, that these “bigwigs” were assembled at Edinburgh to give evidence or opinion in the great trial of Gillespie against Russell. The issues put to the jury were, “Whether the defenders are tenants of certain minerals in the lands of Torbane Hill belonging to the pursuers under a missive of agreement? and whether in the course of the period between the term of Candlemas 1850 and the month of May 1852 the defenders wrought and put out from the same lands of Torbane Hill a valuable mineral substance not let to them by the said missive, to the loss, injury, and damage of the pursuers?” and the damages were laid at ten thousand pounds.

This, in simple language, amounted to this: Gillespie had let to the Russells certain lands, with the right to dig coals; but the Russells, after they got their lease, extracted another substance preferable to coal, for the distillation of paraffin. Mr. Gillespie considered naturally enough that having let the land with the right to dig for coals, the extracting of another mineral for the purpose of making a mineral oil was the taking away of a property belonging to him; while, on the other hand, the Russells, knowing the value of the substance, and the large revenue it was producing, claimed a right to it as being a kind of coal.

We all know that whatever we do to do well we must do earnestly. It is not a thing taken in hand now and then, by fits and starts, that ever reaches the perfection necessary to give it prominence and raise it above things ordinary.

A London society, simply because it is a London society, is not therefore composed of more talent than a provincial society; nor, if it be, is that talent necessarily more effectually applied than it would be by any other society whatever. But as the metropolis is the centre and focus of the English ordinary population, so we think its learned societies ought to be the centres and foci of all the provincial societies. By this we do not advocate that the London societies should at all control the actions of any of the other societies; but we can not but think that the greatest good would arise from a combination of all the provincial Geological Societies and Field Clubs with that which ought to be their natural head—the London Geologists' Association. If the Geological Society itself could be made the great centre of attraction, so much the better; but the exclusive nature of that institution, and the antique system upon which its laws and regulations are founded, seem to prohibit, at least, for the present, any hope of its giving that invaluable help which it has all the materials in its hands for doing.

Four years have elapsed since I first commenced my researches among the Carboniferous Brachiopoda of Great Britain ; and I should certainly by this time have completed my task, had not the unfortunate delay in the publication of the last two or three volumes of the Palæontographical Society induced me to undertake other work which would not require to lie printed and unpublished for upwards of one year and a half. My monograph cannot, consequently, be completed or entirely published for some time to come, perhaps a year or more; but as my researches in connection with the subject are almost ended, since the whole series of species at present known have been as carefully examined as my means and materials would permit, it may, perhaps, be as well that I should at once expose the results of my laborious enquiry, in the hope that by so doing some further assistance and advice may be proffered; which might enable me to make the monograph still more complete, and at the same time admit of my correcting in the concluding pages those unavoidable mistakes which have been commited during the interval which has elapsed since the commencement of its publication.

It may be thought by some while perusing the accompanying catalogue that the work to be gone through was but small in comparison with the time employed, but such would be an erroneous assumption, and a sad return to the numerous friends in England, Scotland, and Ireland, who have so zealously afforded their valuable and valued assistance, by incessantly ransacking the country in order to obtain every possible specimen that might assist and tend to complete the history of British Carboniferous species.

Our knowledge of the limits of animal life have been notably extended during the year which has just departed. Air, blown upon an adhesive surface by the aeroscope on the summit of Etna, twelve thousand feet above the sea level, has been found to contain large quantities of Diatomaceæ; and thus the presence of a zone of life has been discovered to us, soaring not only above the limits hitherto fixed, but above the range of physical phenomena in the mountain itself.

And now the ocean-depths have given up a secret as marvellous. We are taught that at a depth below the surface nearly as great as the height of the infusorial zone above it, animals as high in the scale of being as starfishes are enjoying life. The one discovery is a fitting pendant to the other, and yet, how great is their difference! In the one case the extreme ratification of the atmosphere seemed to our notions to render life impossible; in the other, the enormous pressure of the opposite element, which in the homes of these starfishes must amount to at least a ton and a-half on the square inch, is so greatly at variance with our belief, that we are confounded at the very outset of the inquiry. The capability in an animal so well accustomed to air as the starfish—whose ordinary domain is the seabeach—to exist without it, and its inherent power of withstanding a pressure that would upon the surface grind a rock to powder, are studies replete with instruction and value—studies which can be turned to a good geologieal account, and made to bear reference to a past fauna as well as to a living one.

In many respects the plants and animals of the coal differ much from forms now living. It is probable that the greater part of them are even of different groups or families from the existing ones. But the ferns at least show strong traces of affinity. Here and there we meet with the young fern-leaves coiled up as they now lie on the heather, ready to unfold on the return of spring. We all know these “Bishops' crooks” that nestle in the bottom of the fern-baskets; and when I saw a grand specimen in Mrs. Stackhouse Acton's cabinet (it now graces our museum in Jermyn Street), with the delicate coil of pinnæ, every leaflet in its place, I almost leaped for joy. It was from the Le Botwood coal-field. There is one figured in this work, vol. iii, p. 460 (but the finder has not yet been told, I think, what his fossil is): it is from South Wales, and a beautiful specimen.

Our space was too crowded last month to give the necessary figures of the ferns; and it is but limited now. The leaves or fronds of the delicate Sphenopteris, mentioned p. 101, are very abundant. There are a number of species. S. elegans, S. crassa, and especially S. affinis occur in the lower coals, beneath the mountain limestone of Scotland;—S. artemisiœfolia, S. Honinghausi, S. linearis, S. trifoliata, are all characteristic of our upper coals, and the two last are found in France and Germany.

The district of which it is the object of the present paper to describe the principal geological features, has within the last few years attracted an extraordinary amount of interest and attention, as well from scientific observers as from those who are always seeking some fresh outlet for the investment of their capital. Until a period so recent as little more than twelve years ago, it was only for its fertile meadows and picturesque scenery of hill and dale, that Cleveland had gained any celebrity; but a metamorphosis so truly marvellous has since that time taken place, that it is already entitled to be associated with the most productive iron-making districts in the United Kingdom, and what, in all probability, will be its future position in that respect I shall not now venture to predict, although present circumstances would seem to indicate that, at no very distant day, the great iron-fields of South Staffordshire and South Wales must give place to their youthful opponent in the north.

The discovery, or more properly speaking, the development of the great ironstone deposits of Cleveland in 1848 has given such a stimulus to the iron manufacture of the district, and indeed, of the country, as has seldom been experienced by any other branch of trade. The present flourishing town of Middlesburgh, which, with its new environs, has a population of nearly twenty thousand, for the most part dependent on the iron trade, was, forty years ago, represented by one solitary farmstead, with a census of five inhabitants: and in like manner have all the surrounding villages in the neighbourhood of the new works and mines multiplied their former dimensions with amazing rapidity.

In the number of your journal for October, 1860, I read with great interest a paper by Dr. Watson “On the Metalliferous Saddles of Derbyshire and Staffordshire.” The Doctor says that, though well known to the miners, he believes these saddles have not hitherto been described by any geologist. If he will refer to the Journal of the Geol. Soc., 1857, p. 233, he will find a paper “On the Mines of Namaqualand,” in which I think he will recognise a description of these deposits under the name of “metallic axes.” With such modifications as the difference in the strata and their metallic contents requires, his description would nearly apply to what I said.

The strata in which my axes occur are gneiss and gneiss-granite with occasional beds of magnesian and micaceous rock at Springbok Vontein and Concordia, and micaceous and calcareous rock, with gneiss at Kodas. The saddles (a better name than mine) in all the productive mines were folds in the strata, with fissures of various sizes and directions intersecting them. The one was in some cases more abundant in the planes corresponding to the original bedding of the rock: this was strikingly the case at Concordia, where the main dip was north and the disturbed one south—the strike of the rocks being nearly east and west. (Sec. 1 and 2).

Was there a deluge? It is not to advocate any new reconciliation theory we ask this question; it is not to urge afresh some supposed contact with a comet (if we have just passed through the tail of one, at most the harm we got was a few heavy showers); nor is it to show that periodical inundations or oceanic overwhelmings of each hemisphere—north and south—alternately take place every few thousand years. Probably they do. But neither fifty deluges, nor ten thousand, nor a hundred thousand, would make one deluge—A DELUGE. Our purpose then is, to inquire whether there might not have been, once upon a time, a physical natural cause for a deluge. As the crime of the sinner is often the cause of the amendment of the law, so the bold speculator, breaking out from the trammels of established dicta and the fashionable propriety of a safe reserve, may, as Macdougal Stuart in his daring ride across Australia opened out a luxuriant country where geographers predicted a sandy desert, likewise break in upon glorious fields before unknown. We have so many safe respectabilities in geology that an erratic notion now and then cannot do much harm, if it do no good. When we look up to the moon, what do we see? Great ocean cavities and no water in them. It is of no use to say it is ALL gathered up on the other side. We cannot believe that.

We are glad to find tbis interesting and little-known country is likely to be visited by some of the members of this enterprising club. The address recently delivered by the Vice-President, Mr. William Longman, now lies before us, illustrated by a neatly-executed map of the wild volcanic island he seeks to bring, in a special manner, before scientific notice. It is quite surprising to think that a country so rich in the physical phenomena of moving glaciers and active volcanos has “never been explored or even visited” by any traveller who has made a study of such great causes of surface-aspect. Certain work has, however, been done, and what records of it we have been able to meet with are appended to this article. Most of them are books available for study, and for this special work perusal of them will be useful, as no doubt a goodly company of physical geologists will answer Mr. Longman's call; for existing glacial conditions in Iceland are more likely to aid them in learning the operations of the post-pliocene glacial eras, which in Britain have left such abundant records of their existence.

No one who has read the last “Edinburgh Paper,” by Mr. Robert Chambers, “Ice and Water,” can fail to see how greatly our comprehension of the recent arctic condition of the British Isles will be aided by examination of that icy fringe of the northern zone, which has of late so materially influenced our climate, as if we were again menaced with a southerly extension of polar ice.

But there are other causes that have tended to modify animals; stich as habit, use or disuse of any particular organ, food, climate, &c., and these together with the fact that a variation which appears in the parent, at any period of its existence, tends to re-appear in the offspring at the same period, will enable us to account for the metamorphoses of insects, the differences of colour in the young and the adult, the horus of sheep and cattle, &c. If to these we add that of “sexual selection,” we can see why sexes differ in organs and properties. In fact most of the facts in natural history can be explained by this theory; but there are a few which at present cannot, such as the colours of certain larvæ, which are asexual. Even these may perhaps be the effects of the mysterious and unknown laws of correlation of growth and sympathy between different parts.

We must remember that the theory of natural selection is subordinate to, and totally distinct from, that of the transmutation of species; and that if the former should be found wanting it would not effect the latter in the least degree.

The third great argument urged against the theory of transmutation of species is the geological one; and may be divided into two heads.

I said that “all the years invent;

Each month is various to present

The world with some development.”—Tennyson.

Although most of my readers will be perfectly acquainted with the theory proposed by Mr. Darwin to account for the various forms of life that we see on the globe, yet, for the sake of clearness, I will briefly enunciate it.

Mr. Darwin first shows that individuals of the same species vary one with another.

He then shows that, owing to the rapid increase of animal and vegetable life, by which many more are born each year than can possibly survive, there is a continual warfare going on among them for food and other necessaries. This he calls the “struggle for life.”

He then shows that if any animal or plant should have, by variation, any organ or property so modified as to give it some advantage over its fellows in the struggle for life, it will, as a general rule, live longer and produce more offspring; and these offspring will have a tendency to inherit the organ or property modified in the same manner: but if in one of these offspring the organ should be still further modified, it win give him a like advantage over his brethren, and his offspring again will have a tendency to reproduce the organ in its more modified state; and so on. This he calls “Natural Selection.”

I shall now give a few out of many specimens of coal, to show its composition, and so look at it in a practical point of view. For ordinary purposes, there is no doubt the “best” is the best; but whether that best is Welsh, or Newcastle, or Scottish, I do not pretend to say; for the various kinds of coal are suited for different purposes, and what may be refuse in one direction may be of the greatest use in another.

In experiments undertaken with a view to determine what coals were best suited for our steam-navy, Sir Henry de la Beche and his associates tried nearly all the kinds known in Britain, and compared them too with those artificial fuels which are made up from coal-refuse, and are extremely valuable in their way.

I can only give a few examples, and shall refer my young readers—they are older now than when the lecture began, and will not mind a little dry study—to the book itself, if they require more information.

They tried these coals to see how much they held of carbon, which supplies the heat; of hydrogen, which gives the flame; of oxygen, which is worse than useless in the coal, though essential in the air that is to support the combustion; and, lastly, the quantity of ashes left after the coal was consumed.

In our last lecture stress was laid on the fact that coal-beds, unlike mineral veins, are stratified—not injected, or filling cracks in the earth as metals do. And when we use the term stratified, we mean that the materials we are considering—coal, ironstone, sandstone, clay, shale—were all deposited sheet over sheet, layer over layer, principally by the agency of water.

In scarcely any other way, except by water, can we conceive of materials being spread abroad over vast surfaces, in that even and regular manner which we call “stratified.” As a rule, the matters ejected from the mouths of fiery volcanos are only rudely heaped up, and unless they fall into the sea, do not undergo this smoothing, spreading-out process. The sand of the soa-shore however, and the pebbles on its margin, and the mud of its great depths, are truly “stratified;” and if a fertile plain, or a marshy district were submerged in the waters, the materials on that surface would be soon covered over by the ooze and sand and shingle, and would then be said to be “interstratified” with them. In this way coal-beds occur among beds of sandstone and other rocks.

It is seldom that any coal-field contains more than twenty-five or thirty workable seams: and perhaps these altogether do not amount to above eighty or one hundred feet at the utmost, while in South Wales the coal strata are twelve thousand feet thick. The mass, you see, is rock.

The rooks composing the earth's crust contain a history and represent time—a history of changes numerous, varied, and important: changes in the distribution of land and water; in the thermal conditions of the world; and in the character of the organic tribes which have successively peopled it. The time required for these mutations must have been vast beyond human comprehension, requiring, for its expression, units of a higher order than years or centuries. In the existing state of our knowledge it is impossible to convert geological into astronomical time: it is at present, and perhaps always will be, beyond our power to determine how many rotations on its axis, or how many revolutions round the sun the earth made between any two recognised and well-marked events in its geological history. Nevertheless it is possible, and eminently convenient, to break up geological time into great periods: it must not be supposed, however, that such periods are necessarily equal in chronological, organic, or lithological value; or separated from one another by broadly marked lines of demarcation; or that either their commencements or terminations in different and widely separated districts were strictly synchronous.

One of the terms in the chronological series of the geologist is known as the Devonian, that which preceeded it the Silurian, and the succeeding one the Carboniferous period; and these, with some others of less importance, belong to the Palæozoic or ancient-life epoch, or group of periods.

Not a great many years ago the “bigwigs” in England were assembled in conclave, and the élite of science was called before them. There were a great many lumps of a blackish-brown substance on the table, and a great deal of smelling, and burning, and poking of the same black lumps by the same “bigwigs” and learned men. It was the great “Torbane Hill Coal” case.

“The point was in question, as all the world knows, To what the said substances ought to belong.”

Was it pure carbon? Was it carbonaceous shale? Was it shale without much carbon? Was it carbon without much shale? Was it bituminous shale? Was it coal-shale? Was it cannel? Was it coal?

We are afraid to say how many guineas were spent, or how many microscopes were busy in London and Edinburgh. But after all the question was simply this, “What is coal?” We are not going to try to give a definition; but if we can show our young readers (and there are, we hope, a good many of them) a few of the facts connected with the structure, contents, mode of formation, &c., of a coal-field, perhaps we may be able to answer the formidable query, “What is coal?” without calling in the aid of counsel, and our fee is—one shilling. As this is a Christmas lecture for our young friends, we hope our senior readers will not take it amiss if elementary phrases are introduced, and a few woodcuts given to illustrate what they know very well. And perhaps we may be allowed to speak in the first person singular; it is more conversational.