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of time to be traversed by a canal or railway connecting the two seas together.*

It is singular that we should know so little that is authentic or accurate of the Wadi Araba, or the region which intervenes between the Gulf of Akaba*., the other terminal point of the Red Sea, and the great depression of Palestine, considering its perfect accessibility and the frequency with which it has been traversed. Even the little knowledge we flattered ourselves that we possessed, has now vanished. A writer in the 18th volume of this Society's Journal, basing, as I had supposed, his conclusions on well-established facts, had placed its length at 105 miles, and its summit level at 495 feet; but Capt. Allen, R.N., has since shownj that we are altogether ignorant both of the altitude

* The Isthmus of Suez appears at the southern extremity to constitute the trough or hollow which at one time formed the basin of the upper part of the Red Sea. Here it is walled in on both sides by mountain lands, which rise into loftier regions towards the peninsula, and into rounded hills of soft limestone in the direction of Cairo. It is With the level plain alone we are at present concerned: this was first carefully surveyed by the French engineers in 1799, and the error was then committed of supposing the level of the Red Sea 30 feet above that of the Mediterranean. Although its suitableness for canal purposes had frequently been discussed, and it had been examined by Linant and other European engineers resident in Egypt, fifty years elapsed before the mistake of the French was discovered, when Mr. Stephenson made his survey in 1848. The distance by the shortest line from the Mediterranean to the Red Sea is 75 miles; the length of the canal proposed by the French 92 miles. From the high-water mark at Suez to the bed of the bitter lakes, a distance of 13^ miles, the ground is almost even; it is covered with shells and sea-gravel, and rises from 3 to 12 feet above the highest tide. Here a depression, averaging about 16 feet, commences and extends for a distance of 27 miles; the surface of the bitter lakes themselves, which appear fragments of the Mediterranean or Red Sea lowered by evaporation, being 54 feet. From this to the Mediterranean the ground is low and marshy, abounding in pools of salt water. Over the whole of this tract the shells are identical with those now found in the Red Sea, which was probably here united with the Mediterranean much within the historic period. The question of its practicability for a canal was, until 1850, argued under two assumed difficulties, which have now both vanished—the navigation of the Red Sea before the introduction of steamers, and the difference of the levels of the two seas. The French engineers considered a canal perfectly practicable, and estimated the expense at 700,000/.; and Mr. Maclareu, who first presented us with their views in an English dress, concurs with them in opinion. Linant and Henderson agree as to the practicability, but double the charge. Capt. Vetch considers the canal will cost 2,500,000i. Capt. Glascock and Mr. Galway regarded it as wholly impracticable. Col. Chesney, M. Prony, M. Michel Chevalier, consider the canal practicable in a country where labour was cheap, and no physical difficulties existed. It seems singular that any doubt should be suffered to remain on a question of such supreme importance. The introduction of screw-steamers would permit the vojage to be made in one vessel from Europe to India; the distance between the two seas being calculated at 20 hours with a speed of no more than 5 miles an hour. At present, coal, which must be carried on camels' backs across the desert, costs 10/. a ton at Suez; ships being thereby compelled to carry the bulk of their coal along with them from Aden and back, to their very great inconvenience.

See Mr. Maclareu's paper, Edin. Phil. Journ., 1825; various pamphlets published in 1842 and 1843; the Reports of the Society of Civil Engineers for 1850-51, Miss Fanny Corbaux' Letters in the Athenaeum, 1851-52; Captain Newbold's visit to the Bitter Lakes ; Journal of the Royal Asiatic Society, London, 1846.

f Trans, of the Royal Geographical Society, 1853, vol. 23, p. 166.

and position of its water-shed. We do not profess to know anything of its geology, or the age of its Upheaval. The islands in the Red Sea doubtless afford abundant evidence of these various changes of level; but, with the exception of the volcano of Gibel-Teer, and of those described by Ehrenberg, in the neighbourhood of Ras-Mahommed, scarcely one of them has been examined or described in modern times. The " Two Brothers," in lat. 26° 20' N., long. 34° 45' E., are set down in the chart as coral islands, about 60 feet above the level of the sea. The sea immediately around them sinks at once to 50 fathoms. The Red Sea, around its whole circuit, is walled in by vast masses of mountain, which, down to Judda, in 21° 30' N. latitude, approach close to its shores. On the African side, down to the 16th parallel, isolated hills alone skirt its borders; the higher ranges, 40 or 50 miles off, are seldom seen at sea; and on the opposite shore, between the same parallels, the land slopes gently in towards the interior of Arabia. The rocks chiefly consist of nummulite limestone—a portion of the vast band so admirably described by Sir Roderick Murchison, as stretching all the way, in one unbroken line, from the Bay of Biscay to the shores of Aracan, for nearly one-third of the circuit of the globe. From the parallel 16 to 12 the mountains on both shores and the islands in the middle of the Red Sea are volcanic. Gibel-Teer, in lat. 15° 30', is still smoking, as it has been since 1774, when visited by Bruce, by whom it is set down as 500 feet in elevation. Dr. Kirk makes it 300 feet; the surveyors place it at 900: so little do we know of a volcano passed by our steamers at least four times every month. A violent eruption, of short continuance, took place in one of the Zugar islands, lat. 15°, in 1846, which was fortunately seen from different points of view by steamers passing in opposite directions, but it has never since been visited. A range of hills, above 14 miles from the shore, to which it is nearly parallel, is laid down in the chart as volcanic on the African side, with a similar range of greater magnitude and of the same character, extending from lat. 12° to lat. 15° 30' on the Arabian coast. Dr. Kirk describes these as extending for about 300 miles to the westward; so that this vast volcanic field, which has scarcely been so much as noticed by geologists, occupies probably an area of above 10,000 square miles, without interruption; and is perhaps the third or fourth in point of extent on the surface of the globe. The only one of all its volcanoes with which we are somewhat acquainted is that of Aden, in the crater of which our troops are quartered. It has been so often described that it is not necessary here to refer to it, further than to state that it has clearly been submerged and elevated again from the waters, since the latest period of its activity. Up to the altitude of 500 feet it is thickly strewed with sea-shells mixed with scoriae and volcanic ashes; and in the bottom of the crater and all around the margins of the peninsula are masses of shells and gravel, the same as now prevail in the sea around, and exactly similar to those on the raised beaches of India and of Suez.

Note by Captain Baines.—The latitude of the Straits of Babelmandeb I do not think correct. I found soundings all the way across just outside the Ked Sea; greatest depth 198 fathoms.

There are, no doubt, many reefs in existence not yet discovered: I reported one in April last, upon which an Arab ship struck.

The height of the water within the Red Sea depends upon the seasons; and after strong N.N.W. winds the shoals in the north part are dry in many places: even the shoals in the centre are influenced in the same way. The Durable Shoal can be landed on at times.

In January and February it more frequently blows strong from S.S.E. up the sea in the lower part, and the contrary from N.N.W. in June, July, and August. —8. B. H.

VIII.—Extract of a Letter from Captain Spratt, R.N., on Crete.

Communicated by Colonel Leake, F.r.g.s.
Read March 13, 1854.

I Made an interesting discovery in the western part of the island, viz., that it has been subject to a series of elevations, amounting to the maximum of 24 feet 6 inches, which occurs near Poekilassos and Suia. In the middle- of the island, at Messara, the Fair Havens, and Megalo Kastro, there is none. The eastern end of the island has dipped a little. The upheaving is towards the western end. I had observed it to be about 7 feet in Suda Bay many years ago; but supposed it to be of a time prior to history, although there was a freshness in the markings which might have induced me to suspect they were of a more recent date. When at Kissamo, I observed that the ancient mole was remarkably high out of the water, and the port almost choked by sand. But the latter is so common an occurrence that it did not open my eyes, although the height of the naked unhewn rocks which formed the mole ought to have done so. On going to Phalasarna I looked for its ancient port, mentioned by Scylax, and in the Stadiasmus as the Emporium ; but I could find no artificial work in the sea. There is, however, a long ledge of rocks, or rather an islet which lies off it, helping to form a natural but not an artificial harbour. This satisfied me in part, till, on examining the ruins, I saw in the plain a square place, enclosed by walls and towers, more massive and solid than those of the city. Pashley describes them without having been sensible of their purpose. I was instantly impressed, for several reasons, that here was the ancient or artificial port, although full 200 yards from the sea and nearly 20 feet above it. My first idea was, that the ancients had the means of hauling their vessels into it as a dry dock; but at last the coast elevation was remembered, and on measuring the sea marks at its upper level here, I found that the bed of this ancient port is now 3 or 4 feet below that level ; so that I had only to imagine the coast again let down 22 feet 6 inches, the amount it has been elevated here and at Grabusa, when the sea would immediately flow into the ancient port, and float any small

has another interest; it establishes the recent origin of this remarkable upheaving of the western end of Crete, which, however, is not surprising, as elsewhere ancient harbours have been lifted into the air, rocks have become islets, and maritime cities or buildings placed many yards from the shore. These facts will enable me to reconcile in some instances the ancient geography with the modern, and thus to verify points otherwise very difficult. For example, Suia is noticed in the Stadiasmus as a town with a good port (itoXis St» Xo! Koxo* £%£i), and as following next

to Pctjkilassos, its position is easily recognized. There are so few of the ports of Crete so described in the Stadiasmus, that I naturally looked for a well-sheltered harbour. Pashley says nothing about it, and to look at the locality, few would hope to find a port. A straight and steep shingle beach, off which there is no anchorage, stretches across the mouth of the valley of Suia, and heyond the points of the hills on either side. These points, however, were sea-cliffs, formerly rising out of the beach, to about the height of 23 feet; and on them the old sea level is shown distinctly by the appearance of the rock, as well as by a line of cylindrical holes, the cells of boring sea-shells, in some of which the shells still remain. Pashley speaks of the town and ruins of Suia as lying on the E. side of the torrent or valley, but takes no notice of the western side, where a little plain within a long ridge of ruined buildings, and nearly 300 yards long and 60 or 70 broad, runs parallel to the shore. This was undoubtedly the tongue of land which sheltered the port lying behind it. The position of the port itself is indicated by a hollow or flat depression of the plain, which depression would even now be overflowed by the sea, if the island was again let down to its old level. Hence it seems evident that this great elevation of the coast must be looked upon as subsequent to the existence of these ancient cities, and subsequent, therefore, to the decline of the Roman

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recognition of this ancient port.

Empire.

IX. — Discovery of the North- West Passage. By Commander
R. M'clure, of H.M.S. 'Investigator' {Gold Medallist).

Communicated by Sir George Back, R.N.
Read November 14, 1854.

It will be remembered that among the many ships fitted out by her Majesty's Government expressly for service in the Polar Sea were the Enterprise and Investigator. Nothing that ingenuity could devise or experience sugsest was omitted in order to fortify them against collision with the ice. They were equipped with a warm-air apparatus, had a large supply of extra stores^ and were furnished with provisions for three years. The first was commanded by Captain Collinson, C.B., and the second by Commander Robert M'Clure; and they were ordered to proceed with all possible dispatch to Behring Strait, so as to arrive at the edge of the ice before the 1st of August. They were to bear in mind that the object of the expedition was to obtain intelligence, and to render assistance to Sir John Franklin and his companions, and not for the purposes of geographical or scientific research.

Furthermore, it was thought "unnecessary to give you more detailed instructions which might possibly embarrass you, in a service of this description; and we have therefore only to repeat our perfect reliance in your judgment and resolution, both in doing all that is possible to relieve the missing ships and in withdrawing in time when you come to the painful conclusion that your efforts are unavailing."

The Enterprise and Investigator left Plymouth on the 20th of January, 1850; and a short trial in the rate of sailing soon convinced Commander M'Clure of the inferiority of his ship, which would consequently be left far astern in the long race before them. A week had scarcely passed when they separated in a gale of wind, and did not again meet till the Investigator arrived at the Straits of Magellan, where the Enterprise had been eight days. Having been towed through by her Majesty's ship Gorgon, the same result took place in the fresh start, and on reaching Honolulu, five days later than her consort, Commander M'Clure had the mortification to hear that Captain Collinson only that very morning had sailed for the North, though not without leaving full instructions for his guidance, to proceed to Cape Lisburne, and, in the event of not meeting at that rendezvous, Commander M'Clure was desired to act entirely on his own judgment,—

"which," he adds, "was the most satisfactory dii ection he could have left me."

Having completed his stock of provisions for three years, calculated, however, to suffice for four, he left Wahoa on July the 4th. He was aware that his commanding officer intended to attain to i70° E. longitude, and 30° N. latitude, before shaping his course up Behring Strait. To pursue the same route would only throw him further a stern; and having accidentally gleaned the possibility of passing through the Aleutian group, or Fox Islands, he resolved, with a full knowledge of the risk, to accomplish it:—

"I made," he remarks, "a straight course from Wahoa, which I believe is not usual, but I was obliged to attempt something desperate."

Adding, "perhaps I may be under the influence of some lucky planet," which many more might have thought, had they been equally favoured ; for, being under a great press of canvas, "not a studding-sail was taken in between the latitudes of 17° S. and 69° N." In fact, when his persevering commander was struggling against baffling winds near the western end of the Aleutian chain, on July 29th, M'Clure was in Kotzebue Sound:—

"It is my intention," says Captain Collinson, Sept. 13th, 1850, "to proceed

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