Science in Arcady

by Grant Allen

In a certain sense, it is quite clear that human life depends mainly upon soil and conformation, to an extent that nobody denies. You cannot have a dense population in Sahara; and you can hardly fail to have one in the fruitful valley of the Nile. The growth of towns in one district rather than another must be governed largely by the existence of rivers or harbours, of coal or metals, of agricultural lowlands or defensible heights. Glasgow could not spring up in inland Leicestershire, nor Manchester in coalless Norfolk. Insular England must naturally be the greatest shipping country in Europe; while no large foreign trade is possible in any Bohemia except Shakespeare's. So much everybody admits. But it seems to me that these underlying causes have coloured the entire local history of every district to an extent which few people adequately recognise, and that until such recognition becomes more general, our views of history must necessarily be very narrow. We must see not only that something depends upon geographical configuration, not even merely that a great deal depends upon it, but that everything depends upon it. We must unlearn our purely human history, and learn a history of interaction between nature and man instead.

From the great central boss of the chalk system in Salisbury Plain, two long cretaceous horns or projections run out to eastward towards the Channel and the German Sea. These two horns, separated by the deep valley of the Weald, are known as the North and South Downs respectively. The first great spur or ridge passes through the heart of Surrey, and then forms the backbone of Kent, expanding into a fan at its eastward extremity, where it topples over abruptly into the sea in the sheer bluffs which sweep round in a huge arc from the North Foreland in the Isle of Thanet, to Shakespeare's Cliff at Dover. The second or southernmost range, that of the South Downs, parts company from the main boss in Hampshire, and runs eastward in a narrower but bolder line, till the Channel cuts short its progress in the water-worn precipice of Beachy Head. Between these two ranges of Downs lies the low forest region of the Weald, and between the South Downs and the sea stretches a long but very narrow strip of lowland, beginning at Chichester, and ending where the chalk cliffs first meet the shore beside the new Aquarium and Chain Pier at Brighton. Thus the whole of Sussex consists of three well-marked parallel belts: the low coast-line on the south-west, the high chalk Downs in the centre, and the Weald district on the north and north-west. As these three belts determine the whole history and very existence of Sussex as an English shire, I shall make no apology for treating their origin here in some rapid detail.

The oldest geological formation with which we have to deal in Sussex (to any considerable extent) is the Wealden: so that our inquiry need not go any farther back in the history of the world than the later secondary ages. Before that time, and for long æons afterward, the portion of the earth's crust which now forms Sussex had probably never emerged from the ocean. Britain was then wholly represented by the primary regions of Wales, Scotland, and Cornwall, forming a small archipelago or group of rocky islands separated at some distance by a wide passage from the nucleus of the young European continent. But by the Wealden period, the English Channel and the Eastern half of England had been considerably elevated above the level of the sea. Great rivers and lakes existed in this new continental region, much like those which now exist in Sweden, Northern Russia, and Canada; and the deposits of sand or mud formed at their bottoms or in their estuaries compose the chief part of the Wealden formation in England. Without going fully into this question (somewhat complicated by frequent changes of level), it will suffice for our present purpose to say that the Wealden consists, in the main, of two great divisions, which form, so to speak, the floor, or lowest story, of the Sussex formations. The first or bottom division is chiefly composed of a rather soft and friable sandstone, which runs through the whole Forest Ridges, and crops out in the grey cliffs of Hastings and Fairlight. The second or upper division is chiefly composed of a thick greasy clay, which forms the soil in the greater part of the Weald, and glides unobtrusively under the sea in the flat shore on either side of Hastings, giving rise to the lowlands of Pevensey Bay and the Romney Marshes. Why the sandstone, which is really the bottom layer, should appear higher than the clay in these places, we shall see a little later.

After the deposition of the gritty or muddy Wealden beds in the lake and embouchure of the old continental river, there came a second period of considerable depression, during which the whole of south-eastern England was once more covered by a shallow sea. This sea ran, like an early northern Mediterranean, right across the face of Central Europe; and on its bottom was deposited the soft ooze of globigerina shells and siliceous sponge skeletons which has now hardened into chalk and flint. A great cretaceous sheet thus overlay the Wealden beds and the whole face of Sussex to a depth of at least 600 feet; and if it had not been afterwards worn off in places, as the nursery rhyme says of old Pillicock, it would be there still. I need hardly say that the chalk is yet en évidence along the whole range of South Downs, and forms the tall white cliffs between Brighton and Beachy Head.

Finally, during the Tertiary period, another layer of London clay and other soft deposits was spread over the top of the chalk, certainly on the strip between the South Downs and the sea, and probably over the whole district between the Channel and the Thames valley: though in this case, later denudation has proceeded so far that very few traces of the Tertiary formations are preserved anywhere except in the greater hollows.

Such being the original disposition of the strata which compose Sussex, we have next to ask, What are the causes which have produced its existing configuration? If the whole mass had merely been uplifted straight out of the sea, we ought now to find the whole country a flat and level table-land, covered over its entire surface with a uniform coat of Tertiary deposits. On digging or boring below these, we ought to come upon the chalk, and below the chalk again, with its cretaceous congeners the greensand or the gault, we ought to meet the Weald clay and the Hastings sand. Wherever a seaward cliff exhibited a section for our observation, we ought to find these same strata all exposed in regular order—the sandstone at the bottom, the clay above it, the broad belt of chalk halfway up, and the Tertiary muds and rubbles at the top. But in the county as we actually find it, we get a very different state of things. Here, the surface at sea-level is composed of London clay; there, a great mound of chalk rises into a swelling down; and yonder, once more, a steep escarpment leads us down into a broad lowland of the Weald. The causes which have led to this arrangement of surface and conformation must now be considered with necessary brevity.

The North and South Downs, with all the country between them, form part of a great fold or outward bulge of the strata above enumerated, having its centre about the middle line of the Forest Ridge. Imagine these strata bent or pushed upward by an internal upheaving force acting along that line, and you will get a rough picture of the original circumstances which have led to the existing arrangement of the county. You would then have, instead of a flat table-land, as supposed above, a great curved mountain slope, with its centre on top of the Forest Ridge. This gentle slope would rise from the sea between Chichester and a point south of Beachy, would swell slowly upward till it reached a height of two or three thousand feet at the Surrey border, and would fall again gradually towards the Thames valley at London. On the southern side of the Downs this is pretty much what we now get, the Tertiary strata being preserved in the district near Chichester; though farther east, around Newhaven and Beachy Head, the sea has encroached upon the chalk so as to cut out the great white cliffs which bound the view everywhere along the shore from Brighton to Eastbourne. In the central portion of the boss, however, almost all the highest elevated part has been denuded by ice or water action. Between the North and South Downs, where we ought to find the mountain ridge, we find instead the valley of the Weald. Here the chalk has been quite worn away, giving rise to the steep escarpment on the northern side of the South Downs, seen from the Devil's Dyke, so that at the foot of the sudden descent we get the Weald clay exposed; while in the very centre of the upheaved tract the clay itself has been cut through, and the Hastings sand appears upon the surface. Moreover, the sand, being upraised by the central force, stands higher than the clay on either side, which forms the trough of the Weald; and thus the forest ridge, which abuts upon the sea in the cliffs of Hastings Castle, seems to lie above the clay, under which, however, it really glides on either side. I need hardly add that this rough diagrammatic description is only meant as a general indication of the facts, and that it considerably simplifies the real geological changes probably involved in the sculpture of Sussex. Nevertheless, I believe it pretty accurately represents the main formative points in the ante-human history of the county.

So much by way of preface or introduction. These facts of structure form the data for the reconstruction of the Sussex annals during the human period. Upon them as framework all the subsequent development of the county hangs. And first let us observe how, before the advent of man upon the scene, the shire was already strictly demarcated by its natural boundaries. Along the coast, between Chichester Harbour and Brighton, stretched a long, narrow, level strip of clay and alluvium, suitable for the dwelling-place of an agricultural people. Back of this coastwise belt lay the bare rounded range of the South Downs—good grazing land for sheep, but naturally incapable of cultivation. Two rivers, however, flowed in deep valleys through the Downs, and their basins, with the outlying combes and glens, were also the predestined seats of agricultural communities. The one was the Ouse, passing through the fertile country around Lewes, and falling at last into the English Channel at Seaford, not as now at Newhaven; the other was the Cuckmere river, which has cut itself a deep glen in the chalk hills just beneath the high cliffs of Beachy Head. Beyond the Downs again, to the north, the country descended abruptly to the deep trough of the Weald, whose cold and sticky clays or porous sandstones are never of any use for purposes of tillage. Hence, as its very name tells us, the Weald has always been a wild and wood-clad region. The Romans knew it as the Silva Anderida, or forest of Pevensey; the early English as the Andredesweald. Both names are derived from a Celtic root signifying 'The Uninhabited.' Even in our own day, a large part of this tract is covered by the woodlands of Tolgate Forest, St. Leonard's Forest, and Ashdown Forest; while the remainder is only very scantily laid down in pasture-land or hop-fields, with a considerable sprinkling of copses, woods, commons, and parks. From its very nature, indeed, the Weald can never be anything else, in its greater portion, than a wild, uncultivated, and wooded region.

Let us note, too, how the really habitable strip of Sussex, from the point of view of an early people, was quite naturally cut off from all other parts of England by obvious limits. This habitable strip consists, of course, of the coastwise belt from Brighton to the Hampshire border (which belt I shall henceforward take the liberty of designating as Sussex Proper), together with the seaward valleys and combes of the South Downs. To the west, the great tidal flats and swamps about Hayling Island cut off Sussex from Hampshire; and before drainage and reclamation had done their work, these marshy districts must have formed a most impassable frontier. From this point, the great woodland region of the Weald, thickly covered with primæval forest, and tenanted by wolves, bears, wild boars, and red deer, swept round in a long curve from the swamps at Bosham and Havant to the corresponding swamps of the opposite end at Pevensey and Hurstmonceux. The belt of savage wooded country, thick with the lairs of wild beasts, which thus ringed round the greater part of the county, shut off the coastwise strip at once from all possibility of communication with the rest of England. So Sussex Proper and the combes of the Downs were naturally predestined to form a single Celtic kingdom, a single Saxon principality, and a single English shire.

It will be observed that this description leaves wholly out of consideration the strip of country about Hastings, Rye, and Winchelsea. It does so intentionally. That strip of country does not belong to Sussex in the same intimate and strictly necessary manner as the rest of the county. It probably once formed the seat of a small independent community by itself; and though there were good and obvious reasons why it should become finally united to Sussex rather than to Kent, it may be regarded as to some extent a debateable island between them. For an island it practically was in early times. At Pevensey Bay the Weald ran down into the sea by a series of swamps and bogs still artificially drained by dykes and sluices. On the other side, the Romney marshes formed a similar though wider stretch of tidal flats, reclaimed and drained at a far later period, partly through the agency of the long shingle bank thrown up round the low modern spit of Dungeness. Between them, the Hastings cliffs rose high above marsh and sea. In their rear, the Weald forest covered the ridge; so that the Hastings district (still a separate rape or division of the county) formed a sort of smaller Sussex, divided, like the larger one, from all the rest of England by a semicircular belt of marsh, forest, and marsh once more. These are the main elements out of which the history of the county is made up.