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the Gulf by virtue of its shorter course to the sea, aided perhaps by favorable 

 crustal warping. The place of the capture was just below the junction of 

 the Tallulah and Chattooga Rivers. The falls and gorge of the Tallulah, 

 difficulties in the paths of many former observers, are explained as the result 

 of the presence of a rock barrier in that river more resistant than the forma- 

 tions the Chattooga was forced to cut through. Other physiographers, 

 notably Hayes and Campbell, had reached essentially the same conclusions 

 in regard to this capture, but it remained for this masterly exposition of the 

 case to set at rest all doubts on the subject. H. H. 



Postglacial Faults of Eastern New York. By J. B. Woodworth. 

 From New York State Museum, Bulletin 107, Geological Papers. 

 Albany, 1907. 



At a number of points in and near the Hudson River Valley, as well as in 

 various points in New England, the relation to one another of glacial striae 

 on each side of certain fault planes shows that the displacements have taken 

 place since glacial times. The so-called tilting of the land after the retreat 

 of the ice has, therefore, been accompanied in this region by the fracturing 

 of rocks in certain zones where the strata have yielded by numerous small 

 step-faults. These have a downthrow to the southwest where the strike 

 of the structures is normal to that direction, and to the south where the strike 

 is east and west. The observations so far made indicate that the ancient 

 shore lines on the eastern side of the Hudson gorge north of the Highlands 

 have been raised a few feet more than those of the western side. Confirma- 

 tion is also given to the supposition that there has been a relative uplift in 

 the north and a downthrow in the south of this area, though it is uncertain 

 whether the degree of faulting is a measure of the extent of the change of 

 level. Further examination of these displacements may furnish data for 

 the exact determination of the amount and nature of the postglacial warp- 

 ing to which the northeastern states have been subjected. 



H. H. 



