safely conclude that it was deposited at the bottom of the sea, inferring no doubt a change of the sea level of at least fifty feet. To shew that such changes imply no very remote antiquity, I will now with the permission of the meeting read an extract from a paper of mine to prove that much greater changes than are sufficient to account for the phenomena in question have taken place within the historical era. I do so with less scruple because I arrive at my conclusions from principles that are quite as archæological as they are geological :— "The phenomenon of submerged forests is nowhere more largely developed than on the coasts of Brittany, Normandy, and the Channel Islands. The great rise of tide, amounting in some places to nearly fifty feet, and the flatness of the shores over which it ebbs and flows, in some places not less than seven miles, afford opportunities for observation probably nowhere else to be found. "The chief peculiarities which distinguish this forest are, first,"The freshness of the wood. When exposed, the wood does not differ from that of other submerged forests in respect of decay. Such was the case with what I observed in the bay of St. Ouen, in Jersey, but Colonel Le Couteur, who lives in that neighbourhood, shewed me the stem of an oak which had been laid bare by a heavy gale, in the most perfect state of preservation. In a communication to the Agricultural Society of Jersey, he thus describes it: After the gale, which had greatly denuded the sands, I had the good fortune to see the stem of one of these ancient oaks. The trunk stood four feet above the peaty soil in which it was firmly rooted; its diameter was about three feet. . . . It was still heart of oak.' "I observed at low water on the shore betwen Granville and Avranches, stems of oak in the attitude of growth in a similar state of preservation, and in the same locality the stem of a large tree standing upright. Being surrounded by water I could not approach it sufficiently near to ascertain the species, but it is known to form part of the original forest. According to the Abbé Manet, these ancient stems are locally termed coerons, and in some places canaillons. The wood is used for economical purposes, such as beams in the roofs of houses, furniture, in which its hardness and dark colour give it the polish of ebony, and for espaliers, 'qui resistent long temps aux injures de l'air et qui portent avec eux leur peinture.'-(p. 63.) "The next peculiarity which distinguishes these forests is, that they contain the ruins of ancient buildings and works of art. I cannot speak as to this from my own observation, but the Abbé Manet has brought forward a great mass of evidence proving their occurrence on the French coast; and Falle, the historian of Jersey, states that there are buildings in the submerged forest of St. Ouen. I can, however, give the authority of Captain (now Admiral) Martin White, R.N., who has executed under the directions of the Admiralty an elaborate survey of this part of the French coast. He informs me that on a shoal which is named in the French charts La Parisienne, he has brought up with the lead, fragments of brick and tile, and is quite satisfied that it has been formed by the ruins of an ancient building. He has also seen under water, lines running along the bottom, evidently artificial, and which are probably the same as those mentioned by Borlase in his account of the Scilly Isles, which are locally called "hedges," i.e., ancient stone walls, which, he says, ' are frequently seen upon the shifting of the sands in the friths between the islands.' The same author also mentions a straight-lined ridge, like a cause way, running across the old town creek in St. Mary's, which is now never above water. 6 "Another peculiarity of this forest is the great vertical range through which it can be observed. The tide rises and falls, as already noticed, in the Bay of Cancale nearly 50 feet, and Admiral White informs me he has seen, as far as the eye can penetrate below the surface at low water, stumps of trees in situ beneath the sea, with roots shooting out in every direction. He has observed this phenomenon both on the coasts of France and Jersey. These trees could not be less than 60 feet below high water. "The most important point connected with this forest, however, is the precision with which the date of the submergence can be ascertained. "The account given by ecclesiastical historians and metrical chroniclers is as follows: "About the beginning of the eighth century, St. Aubert, Bishop of Avranches, founded a church in honour of the Archangel Michael upon the mount which now bears his name, which was then surrounded by a forest, and was more than two leagues distant from the sea. Being anxious to procure some relics of the patron saint, he sent two priests to Mount Garganus, in the south of Italy, for a portion of the red altar cloth which the Archangel had left when he visited that place, and of the marble of the altar upon which he stood. During their absence, according to the Père de Moustier, in his Neustria pia, Deo permittente mare sylvam quantumque esset superavit et prostravit replevitque arena locos Monti Tombelino adjacentes; nuntii autem reversi 16 Octobris saltus arena refertos adeo mirati sunt ut novum orbem se ingressos putaverunt.' The Abbé de la Rue, in his Essai Historique sur les Bardes, vol ii. p. 363, quotes an ancient poem by Guillaume de St. Pair, a monk in the monastery of Mont St. Michel, who flourished in the twelfth century, who says that what was then sand was formerly a forest : 'Ceu que or est mer et areine En le forest avait un Mont,' &c. are "But in monkish historians and metrical chroniclers we naturally apprehensive of finding legends for history, in explanation of appearances the origin of which is unknown. Professor de Hericher of Avranches, in his work entitled Avranchin Monumentale et Historique, quotes certain ancient MSS. preserved in the public library in that town which belonged to the Benedictine Abbey of Mont St. Michel, but were dispersed at the Revolution, which give an account of the sudden eruption of the sea, by which the ancient forest was submerged. I availed myself of the opportunity which a visit to that place afforded me of examining them. "The volume No. 34 contains several works in different hands, but all of great antiquity. The one alluded to by M. de Hericher, which he considers from its palæography to have been written in the ninth century, has for its title, Incipit Revelatio Ecclesiæ sancti Michalis in Monte qui dicitur Tumba in occiduis partibus sub Childeberto Rege Francorum, Auberte Episcopo.' The account contained in it is as follows: Qui primum locus sicut a veracibus cognoscere potuimus narratoribus, opacissima claudebatur silva longe ab oceano ut estimata æstu millibus distans sex abditissima præbens latibula ferarum . . . . Mare quod longe distabat paulatim assurgens omnem silvæ illius magnitudinem virtute complanavit et in arenæ suæ formam cuncta redegit . . . . Quasi novum ingressi sunt orbem quam primum veprium densitate reliquerunt.' M. de Hericher, unwilling to admit an actual change of level, supposes that the distance 'ab oceano æstu' refers to low water, and as Mont St. Michel is six miles distant from it, concludes that no change has taken place; but the account of its having been surrounded by wood leaves no room for such a supposition. "According to Père de Moustier, the return of the messengers took place the 16th of October, 709. This date agrees with that assigned to the event by the metrical chronicle quoted by the Abbé de la Rue, who observes, 'Ces revolutions durent avoir lieu suivant la poëte sous l'episcopat de St. Auberte et sous le règne de Childeberte.'-(Vol. ii. p. 303.) "The Abbé Manet states that during the great gale of the 9th of January, 1735, the violence of the sea' sur les gréves de Mont St. Michel fit sortir des gables une quantité prodigieuse de ces billes qu'on y trouva presque toutes conchées du Nord au Sud.'—(p. 53.) This is exactly the position in which the sea, rushing in to fill up a sudden depression, would lay the stems, as the Bay of St. Michel, or Cancale, is open to the north." So far the extracts from my paper. The Abbé Manet attributes the circumstance of the direction in which the buried trees of this vast forest are laid to a violent gale of northerly wind; but, as I learned upon the spot, many of the trees are of vast size, and of oak. Such was that which I examined in the sands near Avranches-the stump of a large tree, with the roots shooting out in every direction. It and many similar examples must have been broken over near the roots. Such effects appear to me to require an agent more powerful than a gale of wind, however violent. This event must have entirely changed the geography of the adjoining regions. The trees seen by Admiral White must have been at least ten fathoms below high water; but luxuriant forests, such as this was, do not grow down to the water's edge of a stormy sea. Ten fathoms is but a part, perhaps a small part, of the actual change of level which took place in October, A.D. 709; but there is no part of the sea between the Channel Islands, St. Maloes, and St. Michel so deep; hence, anterior to the event in question, they formed part of the continent. I think it extremely probable that the Cassiterides, or tin islands of the ancients, placed by them to the north of Spain, were either entirely or partially submerged. In the latter case, the Scilly Islands are the only ones which agree in geographical position, though not in geographical description. According to Strabo they consisted of ten islands, thickly inhabited, and supplying the ancient world with tin. Now there are no mines to be seen in the islands; but only one lode, and the workings are very inconsiderable. Borlase, in his account of the islands, as well as in his paper on the subject in the "Philosophical Transactions," produces evidence of a change of level of at least sixteen feet, and adds, "See how the sea has multiplied these islands; they are now reckoned 140. . . . But no circumstance can shew the great alterations which have happened in the number and extent of these islands more than this, viz., that the Isle of Scilly, from which the little cluster of these Cyclades take the name, is no more at present than a high rock of about a furlong over."-(Phil. Trans., vol. xlviii., p. 55.) sent. With such proofs of change of the sea level during the historic period, no safe inference can be drawn with regard to duration from the occurrence of marine remains at a different level from the preNeither can we reason on the length of time necessary to effect changes by the levels of a river in a settled country; the rights of property prevent the deviations which constantly take place before the banks are taken possession of. I do not think, therefore, that any new light has been thrown upon the antiquity of the human race from the occurrence of works of art in fluviatile or marine gravel at a different level from that of the adjoining rivers or seas. Although, however, these recent discoveries throw no new light on the actual length of time when they were deposited, yet when we consider the extreme rarity of human remains when compared with those of the other cave animals, or the rudeness of the stone implements compared with those of the valley of the Clyde, it appears to me that they belong to the earliest portion of the stone period, that which first followed the appearance of man in the earth, or to use the somewhat old-fashioned, but I consider true language, “the creation of man." |