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But it is probable, that the great philosopher alluded to the partial destruction of the Atlantica insula, mentioned by Placo as a distant tradition of his days. It was effected by an earthquake and a deluge, which might have rent asunder the narrow isthmus in question, and left Britain, large as it seems at present, the mere wreck of its original fize. The Scilly ises, the Hebrides, Orknies, Schetland, and perhaps the Feroe islands, may possibly be no more than fragments of the once farextended region. I have no quarrel about the word island. The little ifthmus, compared to the whole, might have been a junction never attended to in the limited navigations of very early times. The peninsula had never been wholly explored, and it passed with the antients for a genuine island. The correspondency of strata on part of the opposite shores of Britain and France, leaves no room to doubt but that they were once united. The chalky cliffs of Blancnez, between Calais and Bologne, and those to the westward of Dover, exactly tally: the last are vast and continued ; the former short, and the termination of the immense bed. Between Bologne and Folkstone (about fix miles from the latter) is another memorial of the junction of the two countries ; a narrow submarine hill, called the Rip-raps, about a quarter of a mile broad, and ten miles long, exrending eastwards towards the Goodwin Sands. Its materials are boulder-stones, adventitious to many strata. The depth of water on it, in very low spring tides, is only fourteen feet. The fishermen from Folkstone have often touched it with a fifteen feet oar; so that it is juftly the dread of navigators. Many a tall ship has perished on it, and sunk instantly into twenty-one fathoms water. In July 1782, the Bellille of sixtyfour guns ftruck, and lay on it during three hours; but by starting her beer and water, got clear off.'
If we survey the situation of England and Ireland, we shall find vast bays on the western side, trending west and northweit. The chain of islands from Ireland to Iceland, includ. ing the western islands of Scotland and the isles of Feroe, are obviously the remains of a vast continent, partly overwhelmed, and of which the highest lands are only visible. This is the opinion of our author; and it is so obvious from inspection only, that it could not escape a philosophical geographer : it is confirmed by the enquiries of the mineralogist, who genesally finds the fides abrupt and craggy, and the strata frequently corresponding to those of the neighbouring island. We have already remarked, that there seems to have been a continued motion of the sea, from the equator to the poles ; and, from the fituation of our island, this motion must increase the impetus of the sea on its western coait; for, whether by increasing the bulk, and consequently the momentum of the northern Atlantic, it acts directly on the more, or rever
berating from the solid barrier of the frozen ocean, it indi. rectly increases the impetus; yet in either way, it must produce the same effect. In this view then, we must consider the British Channel as a vast bay, in which the sea has followed its usual course. In every part of the English Thore we find marks of an incroaching tide; and the rocks of Guernsey consist of primæval granite, which composes fo large a share of the adjoining continent. The German Ocean was another bay, in a contrary direction, derived from the reverberated current; and the old isthmus, as Mr. Pennant obferves, was broken through by the united force of those opposite tides. cannot think that it was chiefly effected by the northern current, though the tides at present meet in the English channel ; for we are informed by Dr. Wallis, that they formerly met in the German Ocean, and, by their concourse, formed the Dogger Banks, off the coast of Zealand. To allege that the Teverberated current was not so strong as the direct, might be an unfair argument, because it depends on our own opinion ; but there are better proofs of its inferior power, viz, the want of harbours on the eastern coast, which Mr. Pennant has properly noticed, without any view towards an hypothesis; and the existence of considerable flat grounds on the same coast, now forsaken by the sea. Mr. Pennant has mentioned, that the destruction of the isthmus must have occasioned the sea to have retired from those flat grounds which it had occupied before that event; but we think the consequences must have been more extensive. On the flat parts of the western coast we find marine bodies, and are consequently led to suspect, that the formation of the British Channel must have contributed to drain them, though it would not affect the deeper harbours. Again, it is highly probable, that the same con. vulsion must have leffened the force with which the tide was driven up the Baltic, and contributed to draw off the waters reverberated from the icy barrier, so as to lessen the White Sea. By these united causes, the gulfs of Bothnia and Finland were produced, which had been before streights, and formed a marine communication between the German and Arctic Oceans, to the East of the north cape. On the coasts of Kent, the changes we have mentioned are evident; and the luxes and the refluxes of the tide seem to have raised the land very confiderably. In our late review of the Philosophical Transactions, we mentioned the valt depth at which the water was at last found in Languard fort. The superincumbent parts were sand and clay; and that the water was pressed and confined by additional weight, is evident from the fact, that when the workmen arrived at the spring, it soon arose to the level of the present surface.
This feparation certainly happened beyond the reach of historical records, though Dr. Wallis is willing to believe that it gave occasion to Plato's account of the submersion of his famous Atlantica. We readily believe that this history is not entirely fabulous ; and that a vast peninsula, separated from the continent, may at a distant period, and in other countries, have been exaggerated into an event, similar to that which he has related; but there are some circumstances in the history which do not properly suit with this event. Plato exprefly says, that his Atlantica was five days fail from the British illand; and that the sun did not set there for thirty days together. These two distinctions seem to point out some country far north of the extremes of Britain.
This enquiry has led us so far, that we can only remark in general on the other parts of our author's imaginary voyage. If his observations respecting the extensive woods of the northern islands are well founded, we must suppose that they were once a part of the main land, or that some species of trees, which are now extinct, but which were capable of bearing both the spray from the billows, and the great cold, then exifted. Either of these circumstances are highly probable ; but we have known some instances where foflils have been mistaken for wood; and would recommend a farther examination of these apparent trees.
Mr. Pennant still adheres to the former opinion, that America was peopled from the eastern coast of Asia; and his au. thority has induced us again to examine the question, with all the necessary attention. But we see not the least reason to change our sentiments. Naturalists must at last decide. It is sufficient to allege, that the present inhabitants of the opposite continents are very different from each other. The Americans in that part resemble the Greenlanders; and this race at Nootka Sound joins another different from it, and from all the inhabitants of Afia. Mr. Pennant has ielećied those customs which are similar ; but they are so general, as to destroy even the probability that one nation is derived from the other,
There is another subject, on which we differ from Mr. Pen. nant and some other philofophers of considerable judgment, viz. the former situation of the adjoining continents of Asia and America. He thinks that they were once nearer to each other,; but, in the ninety-first page of the volume before referred to, we lated the reasons which we thought supported the opposite opinion. If our author wishes to establish by this
means, his sentiments respecting the population of America, he must be aware, that this distance is not too great to confine the inhabitants ; but that even a less would prevent the parsage of many animals. If we examine these, and their several natures, we fall find the source of population till more obscure than before. We need not again allege the reasons for our opinion, and we have little to add to them. It is probable, that the general effect of volcanos is to raise the land above its ordinary level, and consequently to gain upon the sea; if this be the case, we shall find on the fores of both continents, marks of these operations. It is equally certain, that they sometimes contribute, by altering the ballance, to produce the opposite effect ; but, so far as we can perceive, they gain on the land in those spots on which their ravages are exerted, and the inundations are in more diftant places.
It is with more reason, that our author supposes a great part of North America to be gained from the sea ; and this has been chiefly effected by the sea bursting through the land to the south of Florida, so as to form the gulph of Mexico, leaving only the high grounds in the form of islands, the greater and less Antilles, or, as we choose to call them, the Windward and Leeward Islands. This dereli&tion is particularly perceived on the neighbouring coasts of the Floridas and Carolinas; but is obvious in very distant countries. We surpect, with our author, that America is a new world, in more senses than is commonly understood. The following description is highly curious; and the reader will perceive, that it may be employed to eitablish some very important questions.
• I must here mention the adventitious fruits, such as nuts and other vegetable productions which are brought by the waves to these thores, those of Feroe and the Orknies, from Jamaica and other neighbouring parts. We must have recourse to a cause very remote from this place. Their vehicle is the gulphstream from the gulph of Mexico. The trade.winds force the great body of the ocean from the westward through the Antilles into that gulph, when it is forced backward along the shore from the mouth of the Misisipi to Cape Florida ; doubles that Cape in the narrow sea between it and Cuba, and from Cape Florida to Cape Cannaveral suns ncarly north, ai the distance of from five to seven leagues froir fhore, and extends in breadth from fifteen to eighteen leagues. There are regular foundings from the land to the edge of the stream, where the depth is generally feventy fathoms ; after that no bottom can be found. The foundings of Cape Cannaveral are very steep and uncertain, as the water shallows so quick, that from foriy fathoms it will immediately leffen to fifteen, and from that to four or less; Co that, without great care, a ihip may be in a few minutes on
fhore. It must be observed, that notwithstanding the golphstream in general is said to begin where foundings end, yet its influence extends several leagues within the foundings; and vefa fels often find a considerable current setting to the northward all along the coast, till they get into eight or ten fathom water, even where the foundings stretch to twenty leagues from the shore ; but their current is generally augmented or lessened by the prevailing winds, the force of which however, can but little affect the grand unfathomable stream. From Cape Cannaveral to Cape Hatteras the foundings begin to widen in the extent of their run from the shore to the inner edge of the stream, the distance being generally near twenty leagues, and the soundings very regular to about seventy fathoms near the edge of the stream, where no bottom can be afterwards found, Abreast of Savannah river, the current sets nearly north ; after which, as if from a bay, it stretches north-east to Cape Hatteras ; and from thence it sets east-north-east, till it has lost its force. As Cape Hatteras runs a great way into the sea, the edge of the Itream is only from five to seven leagues distant from the cape ; and the force and rapidity of the main stream has such influence, within that distance, over thips bound to the southward, that in very high foul winds, or in calms, they have frequently been hurried back to the northward, which has often occasioned great disappointment both to merchant ships, and to men of war, as was often experienced in the late war. In December 1754, an exceeding good failing ship, bound from Philadelphia to Charlestown, got abreast of Cape Hatteras every day during thirteen days, fometimes even with the tide, and in a middle distance between the cape and the inner edge of the stream ; yet the ship was forced back regularly, and could only recover its loft way with the morning breeze, till the fourteenth day, when a brisk gale helped it to item the current, and get to the southward of the cape. This thews the impossibility of any thing which has fallen into the stream returning or stopping in its course.
• On the outfide of the fream is a strong eddy or contrary current towards the ocean ; and on the inside, next to America, a strong tide sets against it. When it sets off from Cape Hatteras, it takes a current nearly north-east; but in its course meets a great current that sets from the north, and probably comes from Hudson's Bay, along the coast of Labrador, till the island of Newfoundland divides it; part setting along the coast through the freights of Belleide, and sweeping pait Cape Breton, runs obliquely against the gulph-stream, and gives it a more eastern direction: the other part of the northern current is thought to join it on the eattern fide of Newfoundland. The influence of these joint currents rufi Le far felt ; yet poffibly its force is not so great, nor contracted in such a pointed and circumscribed direction as before they encountered. The prevailing winds all over this part of ths ocean are the west an R4