436 



J. Iloftruan, dated Reading, April 5, 1875, respecting the 

 Practice of Cremation amono; tlie Pah-Utes, or Dio-o-er In- 

 dians, of California. (See page 414.) 



Prof. Frazer read a communication on the composition of 

 trap rocks and gave illustrations on a screen, from slices, 

 with a lime light, and various powers of lens. (See page 402 

 and plates 1, 2, 3, 4.) 



Mr. Chase communicated a comparison between the lunar- 

 monthly rain-fall in the United States as indicated by the 

 morning weather-maps for three years, and the Pennsylvania 

 Hospital observations for 43 years. (See page 416.) 



Mr. Lesley said that the members present might be in- 

 terested in the fact that he had succeeded in obtaining a 

 cross-section projection of the two azoic mountain ranges 

 which once occupied Southeastern Pennsylvania, giving for 

 the first time a correct explanation of the structural geology 

 of the gneiss and mica-slate belt commencing at Easton, on 

 the Delaware River, and passing through Philadelphia, Del- 

 aware, Chester, and Lancaster Counties toward Baltimore. 

 The sharp synclinal at the soapstone quarries separates an 

 anticlinal mass to the north from a broader anticlinal mass 

 to the south. The axis of the latter passes through the 

 Fairraount reservoir, in Philadelphia; and a careful colla- 

 tion and projection of the dips observed, (by Messrs. Young 

 and Fagen, aids on the survey,) along the Reading Railroad 

 track, up the west bank of the Schuylkill, upon a base line 

 of vertical section transverse to the general strike, namely, 

 N. 5° E,— S. 5° W. shows that the highest rock now seen in 

 that synclinal originally rode overFairmount at an altitude of 

 about 15,000 feet; and over the northern anticlinal at an 

 altitude of 10,000 feet. The dips of the northern anticlinal 

 swing round from south by east to north in a regular curve, 

 showing that the northern mountain mass declined rapidly 

 eastward, that is towards Easton, where the whole of the 

 azoic sinks beneath the Kew Red, of New Jersey. This 

 mountain, dying down eastward, stopped the normal course 

 of the Schuylkill from Reading to Chester ; and the present 



