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while, further, the Middle Lias is largely devoted to fruit

growing, and is said to be particularly suitable for apples.' Few, perhaps, are aware that a section of a Devonian coral —that is, of a fossil coral belonging to the incalculably distant Primary period—long formed one of the most popular patterns for calico dresses.

The reader with a taste for etymology will be gratified at learning or at being reminded that the county of Rutland is the red land, probably so named from its red beds of Liassic age; that Bristol takes its name from a bridge, and that Bridgwater does not; that not only in England, but " throughout Western Europe, a large proportion of the ‘river names fall into three groups' dependent on three Celtic words, two of which mean simply water and the third signifies running. The continental Oise, Adour, and Rhine correspond to our own Ouse, Adur, and Rye. Though Ouse and Avon, Exe and Axe, and Esk and Usk are practically the same word which takes on numerous other forms, by their multiplicity we have not been saved from an embarrassing frequency in the employment of some of them. He would be a bold innovator who would force one county or another to relinquish the name of its own especial Derwent, Ouse, or Avon. Roads and streets in busy towns may be rechristened in obedience to the exigencies of the Post Office. It is in another direction that rivers have yielded to the influence of the modern spirit. No longer do we find in vogue that pious simplicity which of yore admired the graciousness of Providence in so often placing great cities on the banks of considerable streams. A modern author allows some share in the arrangement to the free will of mankind. Accordingly the present volume gives many interesting particulars as to the circumstances which have determined the choice of human settlements. From a mere computation of names it is inferred that our an

cestors did not avail themselves of bridges until a com

paratively recent period in our history. There are many more “fords' than bridges' in the designation of wellknown towns. No doubt we may suppose that in times prior to civilisation the freedom of bare limbs was as much prized by the whole population as it is still delighted in by children. Covered carriages and other appliances for warding off a deluge of rain were not in use, so that neither for themselves nor for their costume would people be afraid of water. The inconvenience of conveying heavy properties through the bed of even a shallow stream must have seemed much lighter to the early folk than to us, because, if we may argue from records coming down to not very distant times, so-called roads were often little better than quagmires. It must often have been more cheerful to wade in a stream than to plough the way through swampy ruts. Apart from difficulty in the art and the high cost of bridgebuilding, a bridge itself is of little use except as a link between the stretches of a practicable road at either extremity. Though such an obstacle as a river naturally excites in the human mind a desire to get to the other side, there are conditions of society when the facility of a bridge may have seemed by no means a thing to covet. The beloved neighbour on the opposite bank will perhaps use it to pay a visit uninvited to the bridge-builder. How such a feeling operates may easily be understood from quite modern discussions as to a submarine tunnel, an under-water bridge between

Two mighty monarchies,
Whose high upreared and abutting fronts
The perilous, narrow ocean parts asunder.'

It is true that at a ford Nature itself supplies an easy transit. But at such points neighbours would grow up in that intimacy, that knowledge of one another, which not always but most often leads to the abatement of suspicion, the softening of asperity, the recognition of possible good qualities even in a foe. Where no friendliness resulted, such as to make the ford a desirable place of forgathering, the necessities of self-defence would lead to fortification of the passage, and in this way establish the nucleus of a town or future city.

The military treatment of a river footway is incidentally mentioned by Lord Avebury as throwing a side-light upon a wider subject than the comparative antiquity of British towns. To make possible the laying down and piling up of the successive sedimentary strata from the Primary period to the Quaternary, the changes of elevation relatively to the sea-level which our island has undergone must obviously have been numerous. Of these, to some investigators the latest will seem by no means the least interesting. At many points round our coasts there are submerged forests, the timber of which belongs to well-known existing species. Visitors to the shore are familiar with the débris which from time to time the waves tear up and scatter about. These beds have yielded remains of animals, such as the

elephant, which are no longer wild in our woodlands. It is evident, then, both that tolerably ancient conditions are represented, and that the land on which the trees grew and over which the animals roamed must have sunk, and sunk very considerably. But a later and opposite movement leading to elevation instead of depression is attested by the presence of raised sea-beaches at various parts of the coast. Whether we regard these changes as representing an undulation in which solid rocks are concerned instead of water, or think of the earth's crust as acting like a see-saw, so that one tract is rising while another is sinking, the process, according to all modern experience, in our land is excessively slow. To this slowness a ford and a fortification are very ingeniously made to bear witness. East, but not west, of Bowness the Solway Firth is fordable at low water. It is at Bowness that the Roman Wall ends. At the time of its construction, what would have happened had the land been at a lower level than it is now? As a barrier to fording ten or twelve feet in depth of water are almost as adequate as ten or twelve hundred. A small depression, therefore, would have saved the Romans several miles of building, by enabling them to end their wall efficaciously more to the east, opposite Rockcliff. Conversely, elevation would have extended the fordable area westward of Bowness, and necessi. tated the extension of the wall or other defensive works in that direction. But of any such extension, it is said, there is no trace, the conclusion of the matter being that, to all appearance,' here, at any rate, there bas been no appreciable change of level for 2,000 years.'

Among the things which every schoolboy knows or ought to know there is one matter which can certainly not be included. Neither schoolboy nor philosopher should be expected to say off-hand how long it has taken to mould the existing scenery of England. Those who have not particularly studied the question are disposed to think that a man of science who gives it an evasive, indefinite answer, is either an ignorant pretender or has some selfish motive for keeping his neighbour in the dark. The antagonisms of geology and theology that such problems once enkindled have died out. All the world is now only anxious to know the right solution. It is nearly forgotten that until half a century ago and later all ordinary education was based on the opinion that the sculpturing not of England alone but of the whole globe, with the evolution or genesis of every organism from the monad to the man, had been comprised within six or seven thousand years. Men of high scientific genius had their eyes fast holden by the requirements of this conception. Yet the old Semitic writers were probably not unstirred by some instinct of the truth, when, pondering over the phenomena of Nature, they declared that the Maker of the universe is great, passing our knowledge, neither can the • number of His years be searched out. In His sight they admit that a thousand years are but as yesterday. For them the foundations of the earth are not so firmly laid but that He who laid them may change them as a vesture, and they shall be changed. Among the oscillations which our own land must have indisputably undergone, an instance has just been considered in which quietude appears to have prevailed for about two thousand years. Such a period, important as it may be in the history of culture, in geological time is quite insignificant. But unfortunately from such an instance we do not even obtain a trustworthy unit of measurement. The time required for large upward or downward movements cannot be calculated from places where the movement has been little or none. To return to the illustration of the see-saw, at the fulcrum the rockingboard is stationary, while its ends are experiencing a considerable rise and fall. If the lapse of time be estimated from the thickness of a stratum, it has to be borne in mind that the thin edges no doubt took as long to deposit as the thick central part. When dated inscriptions in a limestone cavern become covered with stalagmite, the sum in proportion which they temptingly offer must be warily treated. For when it has taken two hundred years for the deposition of a tenth of an inch, one might like to infer that a foot of stalagmite could not be deposited in less than twenty-four thousand years. But it is now understood that the drip which in one place produces one-tenth of an inch may in another part of the same cavern be producing the thickness of a whole foot. Of those aquatic organisms whose skeletons contribute materially to the formation of calcareous rocks, it is now well known that some grow with great rapidity. The denudation which slowly strips the land of one stratum is slowly laying down another in the sea, but it is evident that the two processes are contemporaneous, not successive. The doctrine of evolution requires us to unite such creatures as trilobites, flying reptiles, birds that have teeth, in a common phylogeny with the tens and hundreds of thousands of species still living. The latest researches of science draw closer and closer the bonds which connect the vegetable with

the animal kingdom. It is obvious that the lowest estimate of time required for a line of descent so intricate must be enormous. But even here it is coming to be recognised that specific changes perhaps have not been and need not be quite so indefinitely slow as was once supposed.

These are matters for the biologist and the geologist, but then the astronomer and the physicist intervene. The man in the street may be tempted to think the question rather beyond him when he notes some of the investigations with which it is complicated. It may seem a mere trifle to ascertain how much salt there is in the ocean, and to calculate from the contributions of existing rivers how long it took to get there. There are other important considerations, such as the date when the sun began to warm the surface of our globe (a good while before it was ours), and the date when the moon parted from the earth to begin its business of influencing the tides. Those tides themselves are not to be trifled with, for in addition to tides of air and tides of water we have to take into account Problems

connected with the Tides of a Viscous Spheroid,' darkly hinting thereby at the intestines of the earth, about whose tremblings and distemperature Hotspur and Glendower so fiercely disputed, and about which we are disputing still.

With all these elements of perplexity it is scarcely astonishing that wisdom itself does not inspire us with an entirely restful confidence. Lord Avebury says: “It is, 'indeed, as yet impossible to arrive at any close or even

approximate estimate, and various opinions have been • expressed; but looking at the evidence as a whole, we can . hardly, I think, estimate at less than 100,000,000 years • the time which must have elapsed since the commence*ment of life on our planet.' He might have added that the opinions of experts have variously estimated the interval from 1,000,000,000 down to a minimum of 20,000,000 years, the upper limit being no doubt merely a mode of expression to signify indefinite length of time. These round numbers, 80 vast and varied, are in fact a plain confession of ignorance, showing that cosmogony is still waiting for a true and trustworthy arithmetic.

Whether it may have taken 100,000,000 years or only a quarter as long to develope our existing scenery, the title of Old England’ will in either case be well justified. • Dr. Callaway,' we are told, claims for the rocks forming * the heart of the Wrekin the honour of being the oldest in

England. It is not so much, however, upon these

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