636 



SCIENCE 



[N. S. Vol. XXXVII. No. 956 



Sea would have some value if they were not so 

 inaccessible. The same is true to a greater 

 extent of the phosphatic rocks of cretaceous 

 age which the author describes near Nebi 

 Musa, east of Jerusalem, and near Es-Salt, in 

 Moab, east of the Jordan. These latter de- 

 posits are estimated to have a market value 

 of nearly a million and a half dollars, and 

 perhaps much more. Nevertheless, an Eng- 

 lish company, after spending $20,000 in pros- 

 pecting, abandoned its enterprise, because the 

 deposits are so remote, and because the di- 

 rectors of the Mecca railway imposed such 

 onerous conditions of carriage. The only 

 other valuable mineral product is asphalt, 

 with which the cretaceous strata are largely 

 impregnated, but the quality is not high, and 

 the arid climate, rough topography and dis- 

 tance from the railroad prevent its exploitation 

 at present. In discussing all these formations 

 — salt, phosphates and asphalt — the author's 

 geological observations are of more value than 

 purely economic considerations. 



Throughout the volume Dr. Blackenhorn 

 devotes himself mainly to strict geology. Un- 

 fortunately he has adopted the style of a 

 diary in which his birthday, his bath, Turkish 

 officials and the weather are mixed up with a 

 great mass of minute geological details. 

 These details are arranged according to the 

 chance order in which he happened to see 

 them, and hence are difficult to follow and to 

 interpret in general terms. They serve, how- 

 ever, as a running commentary upon two 

 highly valuable contributions, namely, an ad- 

 mirable and reliable geological map, a large 

 part of which is Dr. Blanckenhorn's own 

 work, and a table which sums up the pliocene 

 and pleistocene history of Palestine. The 

 portions of this table based upon physio- 

 graphic evidence are the part of the volume 

 open to question. A summary of late geolog- 

 ical history as interpreted by Dr. Blancken- 

 horn is as follows: 



Lower Pliocene, or late Miocene. Low stand of 

 Mediterranean Sea. First upheaval of the high- 

 lands of Palestine, accompanied by east-west, or 

 N.W.-S.E. faulting which gave rise to such fea- 

 tures as the separation of Upper and Lower 

 Galilee, the basin of Asochis in southern Galilee, 



and the fault-scarp and plain of Esdraelon be- 

 tween Galilee and Samaria. 



Upper Pliocene. Broad encroachment of sea in 

 Syrian Desert. Small lakes occupying parts of 

 the present area of the Sea of Galilee. Basaltic 

 lava flows of Banias and el-Markab. Comple- 

 tion of first great erosion-phase of rivers. 



Gunz Glacial Epoch. Level of Mediterranean Sea 

 330 meters higher than now. At the beginning 

 of this epoch the depression occupied by the 

 Jordan Valley, Dead Sea, Gulf of Akaba and 

 Red Sea began to take form, while at the end 

 occurred the great movements which gave final 

 form to the deeply depressed graben in which 

 lie these various bodies of water. With this 

 ■went considerable faulting in a N.E., S.W. as 

 well as N. and S. direction. Conglomerates and 

 marls were deposited in the much-expanded 

 predecessor of the Dead Sea. 



Gunz-Mindel Interglacial Epoch. This was a 

 short dry period during which the Dead Sea 

 contracted so far that the thick salt beds of 

 Jebel-Usdum were deposited. 



Mindel Glacial Epoch. Sea 33 to 80 meters higher 

 than now. Culmination of glacial period with 

 small glacier in Lebanon. Highest stand of 

 Dead Sea, which extended from the Sea of 

 Galilee to Wadi Araba. The strand formed at 

 this time is supposed by Blanckenhorn to be 

 represented by what he calls the Haupt Ter- 

 rasse or Terrace of Jericho. In the Jordan 

 Valley he assigns to this a height of 100 to 200 

 meters above the present level of the Dead Sea, 

 at the north end of the Dead Sea a height of 

 50 meters, and at the south end a height of 

 486 meters. His natural inference is that there 

 has been an unequal upheaval at the north and 

 south, and a sinking in the middle. It seems 

 impossible to accept this view, since, as the 

 reviewer has shown in ' ' Palestine and its Trans- 

 formation, " there are terraces at the north end 

 of the Dead Sea much higher than 50 meters; 

 and near the head of Wadi Kuram, in this same 

 region, between Massaba and Nebi Musa, de- 

 posits, apparently of lacustrine origin, are 

 found at a height of approximately 450 meters. 



Mindel-Eiss Interglacial Epoch. A long, dry 

 period during which the Dead Sea fell to 

 approximately the present level. Great erosion 

 and much outpouring of lava. 



Eiss Glacial Epoch. Slight encroachment of the 

 Mediterranean Sea, many lava flows. Slight 

 expansion of the Dead Sea, formation of the 



