SEA, is more properly used for a particular part or
division of the ocean; denominated from the countries it wasses, or from other circumstances.—Thus we say, the Irish sea, the Mediterranean sea, the Baltic sea, the Red sea, &c.
Till the time of the emperor Justinian, the sea was common and open to all men: whence it is that the Roman laws grant an action against a person who shall prevent another in the free navigation or fishing therein.—The emperor Leo, in his 56th novel, first allowed such as were in possession of the land the sole privilege of fishing before their respective territories, exclusive of all others: he even gave a particular commission to certain persons, to divide the Thracian Bosphorus among them. From that time, the sovereign princes have been endeavouring to appropriate the sea, and to withdraw it from the public use. The republic of Venice pretends to be so far mistress in her gulf, that there is a formal marriage every year, between that seignory and the Adriatic.
In these last ages, the British have particularly claimed the empire of the sea in the channel; and even that of all the seas encompassing the three kingdoms of England, Scotland, and Ireland; and that as far as the shores of the neighbouring states. In consequence of which pretension it is, that children born on these seas are declared natural Britons, as much as if born on British ground.—The justice of this pretension is strenuously argued between Grotius and Selden, in the Mare Liberum, and Mare Clausum.
Encroachments by the SEA on the Dry Land. It has been matter of dispute whether the land or the water are gaining upon each in this terraqueous globe, and it is a dispute which seems not to be capable of an easy solution. In many places, it is certain that the sea has gained very considerably, and very recently too. In Britain several remarkable encroachments have been remarked. In the reign of Augustus, the isle of Wight made part of the island of Britain, so that at low water the Britons crossed over towards it with cart-loads of tin; but now the connection is totally cut off, and the isle of Wight is constantly separated from Britain by a channel half a mile wide. And in other places the same encroachments are perceptible. In general, on the eastern coast, the sea has gained ground; while on the southern and western, it has gained in some places, and lost in others. It has gained considerably on the coast of Yorkshire, Norfolk, Suffolk, Essex, and the eastern shore of Kent; as also that of Sussex, Hampshire, Dorsetshire, and Cornwall. Within this last half century also the sea has made large encroachments upon the islands of Scilly, and from May 1766 to May 1767 was observed to encroach 40 inches. It has also encroached upon the coasts of North Devonshire, Pembrokeshire, and Cardiganshire. But, on the other hand, in the southern parts of Kent, in Lincolnshire and Lancashire, the land has gained upon the sea. In Kent, it has retreated from the beach of Sandwich, sunk the small aetuary of Solinus into an insignificant current, and converted a fine harbour, called by the Romans Rhutupis, where their fleet were regularly laid up, into a valley watered by a river. In Lincolnshire it has added a considerable quantity of ground to the coast, and left many thousand acres betwixt the old bank of its
its waters and the present margin of its shore. And in Lancashire, the sands which originally formed the beach of the sea, and were covered every tide with its waters, are now regularly inhabited. They still retain the name given them by the Britons, viz. Meales, or loose quaggy lands; tho', loose and quaggy as they once were, they are now cultivated, and a parochial church and village erected upon them.
From considering these facts, we may doubt whether the sea in fact has gained on the land, or the land on the sea; as what is gained by either on one side may perhaps be lost on the other. Buffon imagines, that the sea is perpetually gaining upon the land, and will at last cover the tops of the highest mountains, leaving its present bed quite dry; but his notions concerning the gradual motion of the waters from one place to another have been so fully refuted under the article EARTH, that it is needless to mention any thing further concerning them in this place. Others there are who argue strenuously for the continual increase of dry land, and decrease of the sea. Their principal argument is drawn from a supposition of the vegetation of stone, and a petrifying quality inherent in sea water.
A Scotch gentleman, who was at Boulogne in the summer 1750, has favoured us with a remarkable instance of this petrifying quality in sea-water. He observed, that the British channel, which washes the bottom of a hill near that place, (commonly called Cæsar's Fort, from a Roman encampment still visible on it, said to have been constructed by Julius Cæsar when he invaded Britain), had worn in thro' a great part of the hill, which consists mostly of mixed sand, with about three or four feet of a strong bluish clay soil above. As the sandy part is washed away, the clay falls down in large masses, and, as the inhabitants there affirm, is petrified by the salt water. In fact, one sees, about 40 or 50 yards within the present high-water mark, a large stratum of rocks, much resembling the black rocks at Leith; and between these and the hill many huge masses of rock, though there appears nothing rocky on the bare side of the hill next the channel. And the inhabitants of Boulogne are every day seen blowing up these rocky masses with gun-powder, burning the stones into lime, and using them also as stones for their buildings. This gentleman, walking one day on the sands, saw a large lump of clay fallen from the hill, and so lying to be washed by the tide. He impressed a mark on it with his stick, which, being soft, it then easily received. But passing the same way about three weeks afterwards, he could not force his stick into the same lump.
From some limestone quarries also in the neighbourhood of Kirkcaldy in Fife, and which are taken notice of under the article QUARRY, it is inferred that stones vegetate, and that the waters of the sea have retreated ever since the deluge. These two causes, say the abettors of this doctrine, in a long series of ages, alter the face of our globe entirely, or rather have reduced the earth into its present form, by creating rocks at the bottom of the sea, and then leaving them in dry land, where they turn into inland mountains. This seems to be the method which nature observes: for all along our coasts there are limestone rocks, and some of them within low-water mark, which have the very same inclination, and the same mixture of petri-
fied sea-bodies, as in the quarry we have described; but since we see rocks of this kind arising out of the sea, we must of necessity ascribe the same origin to such as are more remote from the shore, and left up in the country.
All rocks, therefore, where such extraneous bodies are found, seem to be formed from the common sediment of the sea, as sands of several kinds, with the bones of fishes, stalks of sea-weed, and empty shells, which are all rolled into beds by the agitation of the waters. These different bodies, thus blended together, are, by the violence of the flux and reflux, banked up towards the shore: which is the cause of the inclination or dipping of the rock. No sooner is one stratum laid, than, by a continual accession of the same matter, a second is superinduced; and so on successively, till the mass has reached a certain height in water. These loose materials, as soon as the vegetation commences, are fastened by a very strong cement, and, as at the sight of Medusa's head, begin to assume the consistency of stone. For the petrifacient matter fills up all the interstices, pervades the pores of the most solid bodies, and lodges every where the particles that enter into its own composition; which seems to be a fixed salt, or very powerful astringent, together with a mixture of mineral juices or metallic ores, which run in small veins, like wire, in several places of the rock.
The shells, being of a close and compact texture, and therefore refusing admission to the grosser parts, seem to have received only the finer parts of the mixture, which has converted them into a transparent substance, somewhat resembling crystal. The sea-weeds, of a more porous and spongy nature, have imbibed the whole lapidific matter; which has changed them into a fine white marble, capable of a very high polish. The like may be said of all the other bodies, as they are more rare or dense in their texture, and fitted to receive more or less of the petrifacient matter.
The only difficulty in this hypothesis, and what we must endeavour to surmount, is, that we must conceive the sea to be so high as to cover all the hills where such sea-bodies are to be found. So, in the present case, we must suppose it to have been above 200 feet higher than it is at present. Now, though neither history nor tradition could assist us in the inquiry, yet still the fact may be ascertained from indelible monuments, and more to be depended on than any human testimony whatever. For since our inland hills have the very same inclination, and the same mixture of shells, &c. as the rocks have which stand within low-water mark; what can we think, but that the former once stood where the latter stand now? why may we not conclude for certain, that, according to their distances, they have all successively arisen from the sea, as the only proper matrix for such productions, and the only place, too, where the materials that enter into their composition can be found? In short, by means of these petrified sea-bodies, we trace the waters which drowned the old world, like an enemy who leaves his spoils behind him in his retreat, from the tops of our highest inland hills down to the shore; and there see them all confined within the limits of our present sea, which seems still to be making the proper dispositions for leaving
leaving us. Historians, when all our helps fail, produce medals and gold coins, as an authentic evidence of certain facts; in like manner, we may look upon sea-rocks, turned into inland hills, to be an undeniable proof that our earth hath arisen, inch by inch, from the sea.
The age of man bears so small a proportion to the age of the world, that the insensible changes made on the face of nature pass unobserved. We see so few alterations in our own times, that we conclude, too hastily, that there are none at all; or, when the land makes any encroachments in one place, the sea, we imagine, takes her revenge by inundations in another, and that in this manner their limits are pretty well secured. But this is undoubtedly a very lame account of the matter. For inundations seldom happen, and are but partial; whereas the recess of the waters is universal, and, like the other great laws of nature, acts incessantly at all times. An earthquake in one place, the washing of loose sands and earths in another, may lay some particular spots under water; but these will by no means balance the encroachments of the land, remarkable more or less over all the globe. We will but give two or three instances out of many which with equal facility might be produced.
The island Pharos, according to Homer, who, perhaps spoke from experience, stood a day's sailing with a fair wind from the continent. That island, however, was joined to the land, in very ancient times, by a causeway of 900 paces, and makes now a part of the city of Alexandria. The city of Tyre, before the time of Alexander the Great, and for some ages after, was surrounded with a very deep sea of four stades over; and yet we know for certain, it has been joined to the continent upwards of 1000 years.—Eneas landed at Lavinium, if we can believe Virgil; but Lavinium stands now above 12 miles from the sea, and as rich vineyards and corn-fields as are in Italy must for ever go by the name of the Lavinian shores.—Ostia too has undergone the same fate, and become an inland town. Nothing but the express authority of historians, and its own stately ruins, could convince us that it was the celebrated Ostia built at the mouth of the Tiber.—The same observations may be extended to all the maritime towns famous in ancient history: their old harbours are now all choked up, buried under ground, or deserted by the sea, and left far up in the country.
Nor is there much weight in an objection that may be started in this place, namely, That there are several sea-port towns, famous in the ancient world, which have the same character in our own times. So London, under the emperor Nero, was, as it still is, a rendezvous of merchants, and a place of great foreign trade. But are we sure that these towns, though they have the same names, occupy also the same spots of ground with the old ones? Is it not more probable, that the inhabitants, not out of choice, but absolute necessity, and for the convenience of shipping, draw gradually down towards the sea as the rivers choke up towards their sources? This, we know, has happened to some, and we have great reason to believe the same of all.
"We may produce several very strong circumstances, which, taken all together, will amount to the force
of a direct proof that the land has gained very considerably on our coasts. Whoever views the Carse of Falkirk from Stirling castle in Scotland, will think it extremely probable, that all that champaign country, as the ancients believe of the Lower Egypt, has been gained from the sea, by the vast quantity of sand and mud brought down the river. To confirm this conjecture, whenever the ground is digged in several places thereabouts, they meet with vast collections of shells and other spoils of the sea. A ship's anchor was found, some time since, in the same country, buried under ground, at two miles distance from the Forth. These two circumstances put it out of all doubt, nor need we any further proof of the matter. We have nothing but the name to inform us, that ever Burntisland was surrounded with the sea; but whoever views the situation of that place, will be convinced, that, not many centuries ago, it has been joined to Life by a narrow and flat neck of land to the north. The inhabitants of Kirkealdy, even those of a middle age, remember to have seen the tides flow a great deal higher than they do at present. The truth of it is, our shores are insensibly rising, not only from the huge sand-banks, but from a vigorous vegetation of stone, which prevails, among all our coasts, at the bottom of the sea. For nature is as hard at work now as ever; and it is improbable, that these rocks, where there is such a mixture of sea-bodies, which but just show their heads above water, will occasion as much speculation to future ages as their elder brothers in the inland places of the country do to us.
The encroachments of the land in the frith of Tay are more remarkable, and seem to be of a more recent date. The whole Carse of Gowrie has been, we may say, but a late acquisition from the sea; as the flat face of the country, and names of the towns, sufficiently evince. Most of their towns begin or end with infe, that is, island; as Meg-infe, Infe-tower, &c. probably the very names they went by when they were sand-banks, or islands surrounded by the sea.—Some old written instruments mention Errol as a place standing to the south of Tay, though it stands a long mile to the north of the river at present. The inhabitants of the country have a tradition, that the course of Tay, in former ages, was by the foot of the hills to the north of Errol, and to this day they show the very holes in rocks to which the ships cables were fastened. But if the Tay ran so far to the north, as there is great reason to believe, all the lower grounds to the south of Errol would be drowned, and that frith would be twice, if not thrice, as broad as it is in our time.—The inhabitants of Perth remember to have heard their fathers say, that, in the high hill of Kinnoul, they have seen the remains of staples and rings, with other conveniences for shipping, as in a harbour. At a village two miles above Perth, and far from the Tay, some workmen draining a peat-marsh, found the ring, stock, and shaft, of an anchor, with a great log of wood standing erect in the earth, to which it was conjectured the ships cables were fixed. The children of the workmen were lately alive to attest this fact.
These circumstances make it probable, that the land is continually usurping upon the sea, and also may reconcile us to what follows; for if the limestone quarry in the neighbourhood of Kirkealdy was a
sea-rock, as it undoubtedly was, our frith must have covered twice the extent of ground that it does at present. All the lower part of Fife, for some miles up the country, except some islands here and there, and which are now hills or high lands, would be laid under water. The Lothians must have shared the same fate with Fife: for the very spot on which Edinburgh stands, would be covered with water; the Cattle-rock, Calton-hill, and Salisbury Craig, would be sea-rocks; Arthur's seat would be diminished almost to its head; and, with respect to the coast then, might appear what Inse Keith does to us. Northumberland and the Merse must have been in the same situation with the counties bordering on the Forth. The lower part of these two counties would be deluged with a great sea, whose shores would be five or six miles westward from Berwick. The Tweed must have been so great a frith, that the largest ship in the present navy of England might have gone up the river, as far as Kello, if not farther. We call places by their names which then had none. In this manner we might make the tour of Great Britain, and, by imagining the sea to be 200 or 300 feet higher than it is at present, demonstrate, that our island is larger, by a third at least, than it was at that time.
Such has been the state of our island; in a very remote period of time, no doubt; though perhaps not in the ages immediately succeeding the deluge: on the contrary, it may be presumed, that as many ages must have passed from the deluge to the period we are speaking of as from thence to our own times. For we have all the reason in the world to believe, that, ever since the old world was drowned, the waters have fallen equally in equal times, and not faster at one time than at another as is commonly imagined. The bare rocks on our highest hills show sufficiently both the place where they have vegetated, and that for many ages they have borne the violence of that dreadful element: for it is impossible to conceive, that they could have come out of nature's hands in the miserable and ruinous condition in which they appear. Their ragged tops, tattered surfaces, and rifted sides, are the wounds they have received from an obstinate foe; who, though vanquished at last, has made many furious attacks, and disputed every inch of ground, before he has retreated.
It is very probable, that, in the earlier ages after the flood, the country between the Tweed and the Tay might appear in the following manner. The Cheviot hills to the south, and Lamer Moor hills to the north, would be the limits of the frith of Tweed; the same Lamer Moor hills to the south, and the Lomond hills to the north, would be the boundaries of the frith of Forth; the Lomond hills to the south, and a like ridge of hills to the north of the Tay, would be the confines of the frith; so that in all the space betwixt the Tweed and the Tay there would be three very great friths, with no inland intervening but the backs of these bare hills, which would show like long tongues of land running out a great way in the sea.
In reality, when one views the country around, from any of the high hills we have mentioned, and observes it sloping gradually from the inland parts down to the sea, and on each hand towards the beds of the rivers, one can hardly forbear thinking it was once in
such a situation, and that it still looks like the shore of a great sea, which has now, after a long succession of ages, almost disappeared. For, not only the earth slopes, as we have said before, towards the sea, or towards the rivers; but the very rocks, contrary to their natures, conform themselves to this inclination. The flat rocks, where the growth or vegetation runs horizontally, dip all at one extremity; whereas we might expect to find them all lying in the plane of the horizon. Again, in some kind of flint-rock, where the vegetation shoots directly upwards, the flakes of the stone are all reflected from the perpendicular, and make a very obtuse angle with the horizon, not under 120 degrees, as nearly as can be guessed. Now, it is absolutely impossible to account for such an inclination, unless we suppose that the sand-banks, of which these rocks were originally formed, having been shored up towards the land, by the flux and reflux of the waters, before they were fixed by vegetation."
These are some of the strongest arguments which have been advanced for the continual increase of the dry-land, and decrease of the sea. How far they appear conclusive, we leave to the judgment of the reader.
Luminousness of the SEA. See LIGHT, n° 26.