GEOLOGY. 253 



them, M. Lartet considers to be caused by the proximity of large 

 quantities of rock-salt, or of earths containins^ rich saliferous 

 deposits. Especially is this the case around the Dead Sea, where, 

 from time immemorial, there has been known to exist the Moun- 

 tain of Salt, in the Arabic of which it is believed that the name 

 of Sodom may be recognized. 



M. Lartet has carefully examined the formation of the basin of 

 the Dead Sea, and finds that it was formed at the end of the 

 fcocene epoch, as is shown by the character of the superficial 

 niai'ine deposits in neighboring countries. But before this period, 

 dislocations were produced in the submarine strata ; a fracture 

 opened in a north and south direction, which, by consecutive 

 convulsions, prolonged itself northwards, determining, upon the 

 shores of the Mediterranean, the formation of the mountainous 

 ridges of Palestine, and also producing a narrow and lengthened 

 depression which separates the high table-lands of Arabia. From 

 this depression has sprung the commencement of the hydrograph- 

 ical system of this region. Thus, the Dead Sea, orLake Asphaltites, 

 was formed, from its origin, without any communication with the 

 ocean. 



The level of this lake, as shown by the great extent of horizon- 

 tal layers of marl which have evidently been deposited at a 

 former time, ought at a certain epoch to have been one hundred 

 metres above its present altitude. The consequent extension of 

 the waters of the lake is clearly shown by the sediments, which 

 cover vast surfaces to the north and south of its actual limits. A 

 great change must, therefore, have since occurred in the hydro- 

 grajihical arrangement of the country. Owing to the absence of 

 fossils in the sediments above mentioned, it is imiwssible to assign 

 the exact age of the elevation of the waters of the lake. Never- 

 theless, by reckoning the ijrobable duration of the jDhenomena 

 which have preceded and followed this important phase in the 

 history of the Dead Sea, the time of its occurrence can be fixed at 

 about the end of the tertiary or the beginning of the quaternaiy 

 period. 



In the diminution of the extent of the lake, M. Lartet imagines 

 he can discover an evidence of the disappearance of former glac- 

 iers. This he thinks well accords with those traces of ancient 

 glacier moraines, upon which Dr. Hooker believes the cedars of 

 Lebanon now grow. 



During a later period, phenomena of a different nature have 

 otherwise altered the physical aspect of this country. At the 

 north-east of the Dead Sea, volcanic eruptions have produced im- 

 mense flows (coulees) of basaltic rock, portions of which had even 

 overflowed into the valley of the Jordan. These eruptions made 

 Eastern S^^ria at one time a volcanic district equal to that of Au- 

 vergne. Among other smaller basaltic streams, three were found 

 bordering on the eastern edge of the Dead Sea, to the south of 

 the little plain of Zarah. 



Thermal springs, minerals similar to those bituminous emana- 

 tions which have accompanied or followed the volcanic eruptions, 

 and earthquakes still felt in this coimtry, were stated to be the 

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