12 NEW YORK STATE MUSEUM 



metamorphosed, the syenite commonly appearing almost schist- 

 ose. 



The true Beekmantown appears to be absent from the Broad- 

 albin quadrangle so that the Trenton always rests unconform- 

 ably upon the Little Falls dolomite, A series of distinctly trans- 

 itional beds lies between the Potsdam sandstone and the Little 

 Falls dolomite. This formation has been named from the town 

 of Galway where it is best shown and it has been separately 

 shown on the geologic map. Toward the southeast the Pots- 

 dam has at its base a very interesting conglomerate made up 

 of Grenville quartzite fragments from i to 3 feet in diameter. 



The district is remarkable for its faults, no less than 14 

 having been mapped. They are all normal with displacements 

 ranging from 100 to 150 feet. Several of these have been map- 

 ped for the first time, and one of these, the BatcheUerville fault, 

 showing a displacement of 1500 feet, has been traced for over 

 10 miles. The BatcheUerville fault is also of interest because, 

 so far as known, it is the greatest of the Mohawk valley faults 

 with the upthrow side on the east. 



Pleistocene deposits of various types are finely exhibited. 

 There is distinct evidence, as shown by A. P. Brigham, that a cur- 

 rent of ice flow^ing south-southwestward past Northville met 

 another current flowing northwestward past Galway in the vi- 

 cinity of Broadalbin. The lowest land, including the area of the 

 great swamp known as the " Vly," was once covered by a gla- 

 cial lake. 



Adirondacks. Last year I reported the completion of the 

 survey of the Elizabethtown and Port Henry quadrangles by 

 Professor Kemp and Dr Ruedemann and this report is now in 

 press. Professor Kemp has followed this by the survey of the 

 Mt Marcy quadrangle which lies next west. The field work 

 had been done upon the area in former years and the final re- 

 port had been to some degree blocked out. 



This section of the Adirondacks contains many points of 

 special interest. The two summits, Mt Marcy and Mt Mclntyre, 

 which alone of all the peaks exceed 5000 feet, are within it. 

 Of the 16 peaks which stand between 4000 and 5000 feet, 14 

 are also here. The remaining two are Giant, which lies just 

 east, and Whiteface which is a few miles north. It will thus 

 be readily seen that we are here dealing with the culmination 

 of the Adirondacks. 



Careful study of the mountains brings out the fact that in the 



