exhaustion. North of the peninsula the lake has a maximum depth of 1278 ft.; south of it the water is nowhere more than 12 ft., and in some places only 3 ft. The surface level of the lake varies with the season, and recent observations taken on behalf of the Palestine Exploration Fund seem to show that there are probably cyclical variations also (ultimately dependent on the rainfall), the nature and periodicity of which there are as yet no sufficient data to determine. In 1858 there was a small island near the north end rising 10 or 12 ft. above the surface and connected with the shore by a causeway; this has been submerged since 1892; and owing to the gradual rise of level within these years the fords south of the Lisān, and the pathway which formerly rounded the Ras Feshkhah, are now no longer passable.
The slopes on each side of the sea are furrowed with watercourses, some of them perennial, others winter torrents only. The chief affluents of the sea are as follows:—on the north, Jordan and ʽAin es-Suweimeh; on the east Wadis Ghuweir, Zerka Maʽin (Callirrhoë), Mōjib (Arnon), Ed-Deraʽa, and el-Hesi; on the west, Wadis Muhawāt and Seyāl, ʽAin Jidi (En-Gedi), Wadi el Merabbah, ʽAin Ghuweir, Wadi el-Nar, ʽAin Feshkhah. The quantity of water poured daily into the sea is not less than 6,000,000 tons, all of which has to be carried off by evaporation. The consequence of the ancient evaporation, by which the great Pleistocene lake was reduced to its present modest dimensions, and of the ceaseless modern daily evaporation, is the impregnation of the waters of the lake with salts and other mineral substances to a remarkable degree. Ocean water contains on an average 4-6% of salts: Dead Sea water contains 25%. The following analysis, by Dr Bernays, gives the contents of the water more accurately:—
| Specific gravity 1.1528 at 15.5° C. | ||
| Calcium carbonate | 70.00 | grains |
| Calcium sulphate | 163.39 | |
| Magnesium nitrate | 175.01 | |
| Potassium chloride | 1089.06 | |
| Sodium chloride | 5106.00 | |
| Calcium chloride | 594.46 | |
| Magnesium chloride | 7388.21 | |
| Magnesium bromide | 345.80 | |
| Iron and aluminium oxides | 10.50 | |
| Organic matter, water of crystallization, loss | 317.57 | |
| Total residue per gallon | 15260.00 |
The density of the water averages 1.166. It increases from north to south, and with the depth. The increase is at first rapid, then, after reaching a certain point, becomes more uniform. At 300 metres its density is 1.253. The boiling point is 221° F. To the quantity of solid matter suspended in its water the Dead Sea owes, beside its saltness, its buoyancy and its poisonous properties. The human body floats on the surface without exertion. Owing principally to the large proportion of chloride and bromide of magnesia no animal life can exist in its water. Fish, which abound in the Jordan and in the brackish spring-fed lagoons that exist in one or two places around its shores (such as ʽAin Feshkhah), die in a very short time if introduced into the main waters of the lake. The only animal life reported from the lake has been some tetanus and other bacilli said to have been found in its mud; but this discovery has not been confirmed. To the chloride of calcium is due the smooth and oily feeling of the water, and to the chloride of magnesia its disagreeable taste. In Roman times curative properties were ascribed to the waters: Mukaddasi (A.D. 985) asserts that people assembled to drink it on a feast day in August. The salt of the Dead Sea is collected and sold in Jerusalem; smuggling of salt (which in Turkey is a government monopoly) is a regular occupation of the Bedouin. The bitumen which floats to shore is also collected. The origin of this bitumen is disputed: it was supposed to be derived from subaqueous strata of bituminous marl and rose to the surface when loosened by earthquakes. It is, however, now more generally believed that it exists in the breccia of some of the valleys on the west side of the lake, which is washed into the sea and submerged, till the small stones by which it is sunk are loosened and fall out, when the bitumen rises to the surface.
History.—The earliest references to the sea or its basin are in the patriarchal narratives of Lot and Abraham, the most striking being the destruction of the neighbouring cities of Sodom and Gomorrah. (See Sodom.) The biblical name is the Salt Sea, the Sea of the Arabah (the south end of the Jordan valley), or the East Sea. The name in Josephus is Asphaltites, referring to the bituminous deposits above alluded to. The modern name is Bahr Lūt or “Sea of Lot”—a name hardly to be explained as a survival of a vague tradition of the patriarch, but more probably due to the literary influences of the Hebrew Scriptures and the Koran filtering through to the modern inhabitants or their ancestors. The name Dead Sea first appears in late Greek writers, as Pausanias and Galen. At En-Gedi on its western bank David for a while took refuge. South of it is the stronghold of Masada, built by Jonathan Maccabaeus and fortified by Herod in 42 B.C., where the last stand of the Jews was made against the Romans after the fall of Jerusalem, and where the garrison, when the defences were breached, slew themselves rather than fall into Roman hands.
The sea has been but little navigated. Tacitus and Josephus mention boats on the lake, and boats are shown upon it in the Madeba mosaic. The navigation dues formed part of the revenue of the lords of Kerak under the crusaders. In modern times navigation is practically nil. The lake, with the whole Jericho plain, is claimed as the personal property of the sultan.
The medieval travellers brought home many strange legends of the sea and its peculiarities—some absurd, others with a basis of fact. The absence of sea-birds, due to the absence of fish, probably accounts for the story that no birds could fly over it. The absence of vegetation on its shores, due to the scanty rainfall and general want of fresh water—except in the neighbourhood of springs like ʽAin Feshkhah and ʽAin Jidi, where a luxuriant subtropical vegetation is found—accounts for the story that no plant could live in the poisonous air which broods over the sea. The mists, due to the great heat and excessive evaporation, and the noxious miasmata, especially of the southern region, were exaggerated into the noisome vapours that the “black and stinking” waters ever exhaled. The judgment on Sodom and Gomorrah (which of course they believed to be under the waters of the lake, in accordance with the absurd theory first found in Josephus and still often repeated) blinded these good pilgrims to the ever-fresh beauty of this most lovely lake, whose blue and sparkling waters lie deep between rocks and precipices of unsurpassable grandeur. The play of brilliant colours and of ever-changing contrasts of light and shade on those rugged mountain-sides and on the surface of the sea itself might have been expected to appeal to the most prosaic. The surface of the sea is generally smooth (seldom, however, absolutely inert as the pilgrims represented it), but is frequently raised by the north winds into waves, which, owing to the weight and density of the water, are often of great force.
The first to navigate the sea in modern times was an Irish traveller, Costigan by name, in August and September 1835. Owing largely to the folly of his Greek servant, who, without his master’s knowledge, threw overboard the drinking-water to lighten the boat, the explorer after circumnavigating the sea reached Jericho in an exhausted condition, and was there attacked by a severe fever. The greatest difficulty was experienced in obtaining assistance for him, but he was ultimately conveyed on camel-back to Jerusalem, where he died; his grave is in the Franciscan cemetery there. His fate was shared by his successor, a British naval officer, Lieutenant Molyneux (1847), whose party was attacked and robbed by Bedouins. W. F. Lynch, an American explorer (1848), equipped by the United States government, was more successful, and he may claim to be the first who examined its shores and sounded its depths. Since his time the duc de Luynes, Lartet, Wilson, Hull, Blanckenhorn, Gautier, Libbey, Masterman and Schmidt, to name but a few, have made contributions to our knowledge of this lake; but still many problems present themselves for solution. Among these may be mentioned
