48o REVIEWS 



The Charleston Earthquake of 1886 in a New Light. By William 



Herbert Hobbs. (Reprint from Geological Magazine, N. S., 



Decade V, Vol. IV, May, 1907, pp. 197-202.) 



The linear distribution of craterlets and of points of special damage to 



railroad tracks, as determined by Button, leads the author to the conclusion 



that these phenomena indicate the position of faults in the rocks below the 



coastal series. There are two main sets of faults, one treading about 



N. 6s° E., the other about N. 10° W. 



c. w. w. 



Some Topographic Features Formed at the Time 0} Earthquakes and 



the Origin of Mounds in the Gulf Plain. By Wm. H. Hobbs. 



(Reprint from American Journal of Science, Vol. XXIII, 



pp. 245-56, April, 1907.) 



In areas of subsidence, especially during earthquakes, water is squeezed 



upward through fissures and gives rise to forms such as the mud cones and 



craterlets in the deltas of great rivers, to the sandstone dikes and pipes 



observed in many rocks, and to mounds of the "spindle-top" type observed 



in the Texas and the Baku oil-fields. 



c. w. w. 



Itineraires dans le Haut Atlas Marocain. By T^ouis Gentil. La 

 Geographie, Bulletin de la Societe de Geographic, 15 mars, 1908, 

 pp. 177-200, map. 

 M. Gentil has furnished us a sketch of the topographic and geologic 

 observations made during his journeys in a difficult and dangerous area 

 which includes Cape R'ir and Marrakech in Morocco. Most of the systems 

 of sedimentary rocks are represented in this region, together with volcanic 

 and metamorphic formations of somewhat uncertain age. It is a striking 

 fact th'at the rocks show in most cases the features which are characteristic 

 of contemporaneous deposits in the greater part of the surface of the earth. 

 Thus the lower Carboniferous contains limestones with numerous crinoids 

 and bryozoans and the Permo-Trias consists of red-beds with gypsum and 

 salt and of other deposits formed on land or in shallow lagoons. As else- 

 where, the Cretaceous marks a period of extensive sea transgression and 

 may easily be separated into a lower and an upper division. The shelly 

 sandstones of the Tertiary occupy a tract along the Atlantic coast. The 

 author concludes with a summary of the general orography of the north- 

 western corner of Africa. His observations confirm the conclusion of Suess, 

 that there is essential continuity between the structures of northern Africa 

 and southern Spain. H. H. 



