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Lamont. But these are probably exceptions, and the statements are not certain. The average rate must not be put higher than 2% feet. Darwin does not put it higher even for the west coast of S. America, where we have more proof of sudden alterations of level than anywhere else. But such average calculations are quite inadmissible. Rises and falls of very different extent have been observed in various regions. The three upright pillars of the temple of Serapis at Pozzuoli, in Italy, give us an instructive example of this. Quenstedt says of these : * “8 feet up the pillar we find a band of marine shells 8 feet wide, in which many shells in a very well preserved state are still sticking in the holes. These live only on the surface of the sea; therefore the water must have stood at least 18 feet higher than it does at present. Now as the temple could not well have been built under water, two movements must have taken place; the water rose and fell. But this is merely local ; the ruins of the temple of Neptune and the Nymphs, which are 3000 to 4000 feet distant, are under water, and here the upheaval did not take place. In 1807 the pavement of the temple was dry; from that time the water rose gradually, so that in 1845 it stood 28 inches high; in 1852 a decrease took place of about 1 inch a year. The Mediterranean countries are full of such phenomena; on the west coast of Crete beds of shells are found 27 feet above the sea, while 40 miles to the east the ruins of Greek towns can be seen under the water.” At Basin Bridge, on the English coast, forests and Roman buildings * Epochen, p. 827.
have been found 6 feet below the present level of the sea ; and at Morlaix, in France, submarine forests, which sank there suddenly in the eighth century. On the coast of Ireland, at Donegal, a fall of 20 feet has taken place in the last 100 years, for trees, and even old furnaces, now stand under water. At some places on the west coast of Greenland the water already stands above the ruins of the buildings which were erected there by the first Danish settlers." Besides these gradual upheavals and depressions, other sudden upheavals and depressions of considerable extent take place. I add the following example to those already given.” In June 1819 an enormous dam, 11 geographical miles long, 3 broad, and 10 feet high, was formed by an earthquake in the eastern delta of the Indus, on what had been a perfectly level plain; at the same time the town of Sindren, which was one mile off, sank, together with a piece of land, to such an extent that it was covered by water. On the 23rd of January 1855 a tract of land as large as Yorkshire rose from 1 to 9 feet on the south-west coast of the northern part of New Zealand, and the harbour of Port Nicholson rose from 4 to 5 feet. The effects of the earthquake of 1832 in South America were felt for 1200 miles from north to south; the whole coast of Valparaiso was raised at least 3 feet, the whole country, which is half as large as France, showed distinct signs of upheaval. Similar phenomena occurred on February 20, 1835; most of the land was said to have been raised from 4 to 5 feet, but by April it had sunk again 2 to 3 feet. At Valparaiso the land has risen 10 feet in ninety years, in the Bay of Cacao 6 feet in six years, at Panco about 24 feet in about eighty years. The upheavals on this coast are not limited to isolated spots; the greater portion of the western coast of South America seems to be affected by them, and it is not only these historical upheavals which make this coast so remarkable, but it is said that numerous signs of former upheavals have been found in widely scattered localities. The island of Sicily has also risen considerably in recent times; at some places the coast is 200 feet above the former level." One of the books” from which I have taken these data speaks of a discovery made in Sweden in 1819, during the digging of a canal between the Máeler lake and the Baltic, which is looked upon as a proof of the sinking and rising of Sweden. Nails, anchors, and pieces of old boats were found between two walls of rock in layers of rubble and sand; and at a depth of 64 feet a wooden hut was discovered. It was inferred therefore that after the building of the hut this part of the land had sunk gradually to a depth of 64 feet below the level of the sea, that it was then covered with the deposits which were cut through in order to construct the canal, and then rose again.” There seems, however, to be a simpler explanation: according to old records a canal existed in this place in the eleventh century, which was used for some time and
* Pfaff, Schöpfungsgeschichte, p. 288. * See vol. i. p. 439. WOL. II. T
1 Molloy, Geology, p. 282. C. W. E. Fuchs, Die ruleanischen Erscheinungen der Erde, Leipzig 1865, p. 442 seq. O. Peschel, Neue Probleme der vergleichenden Erkunde, Leipzig 1870, p. 89 seq.
* Fuchs, Op. cit. p. 455. * Pfaff, Schöpfungsgeschichte, p. 28 seq.
then fell into disuse, so that the deposits 64 feet deep which cover it may have been heaped up by the wind and the water. Others say that the hut was destroyed by the downfall of a sand-hill. At any rate it is not thousands of years old.' These facts prove that the upheaval and depression of the ground is a very varying geological phenomenon which cannot be averaged, and that no distinct rule can be laid down about it which will hold good for all countries and all times. For just as now the upheaval and depression goes on in different countries under different conditions at different rates of progression, so it may have gone on more or less slowly in different centuries in the same country. If, then, it has been ascertained by observations made in this century that Sweden is rising at the rate of 2% or 4 feet in a hundred years, it does not follow that this gradual upheaval was not greater in former centuries; nor that besides this gradual rise, at some periods and in some places, a sudden rise may not have occurred.” At any rate no trustworthy measure of time can be obtained by this means, and all calculations about the age of the implements and boats found in Scotland and in Sweden, which are based on the rate at which land is rising, are no more than arbitrary assumptions, because the rate of progression is not sufficiently known, and can never be definitely ascertained. It is interesting to know what Lyell has said on this subject. “As no accurate observations on the rise of the Swedish coast refer to periods more remote than a century and a half from the present time, and as traditional information, and that derived from ancient buildings on the coast, do not enable the antiquary to trace back any monuments of change for more than five or six centuries, we cannot declare whether the rate of the upheaving force is uniform during very long periods. . . . As the movement is now very different in different places, it may also have varied very much in intensity at different periods.” In conclusion I will mention an analogous case, which clearly shows how little the changes in the proportion of land and sea can be of use to us as a measure of time. We know that the coast of Medoc in the Bay of Gascony is continually being encroached upon by the ocean. The ancient Noviomagus, which was swallowed up by the waves in the year 580 A.D., lies in ruins under the sea. The rock of Cordouan, on which was a lighthouse, was originally connected with the coast, it is now distant from it about three leagues. Since 1818 the rate at which the sea is encroaching has been accurately recorded. From 1818 to 1830 the sea gained 180 metres of ground. If we average this, we get 15 metres a year, and according to this the sea Principles of Geology, ii. p. 345. Cf. Leonhard, Geologie, ii. 89.
Archiv für Anthr. vii. 276. Corr.-blatt der D. Gesellschaft für Anthr. 1875, p. 18. “The assertions of the recent Geologie Archeologique, in spite of their incomparable assurance, often lead us to suspect that the whole thing is a joke, and intended to mystify antiquaries. What are we to think of the fisherman's hut, with the hearthstone and the bundle of faggots on it, which was found near the Máeler lake 64 feet deep in the earth, and which had been sinking so slowly and undisturbedly for 80,000 years at the rate of 10 inches a century, that hut, hearthstone, and faggots had, marvellous to say, escaped destruction ?” See Lindenschmidt in the Archiv für Anthr. i. 53.
* Cf. O. Schmidt, Oesterr. Wochenschrift, 1863, ii. p. 388. Cotta, Geol. Bilder, p. 49. Pfaff, Die neuesten Forschungen, p. 71.