92 PROCEEDINGS OF THE ACADEMY OF [1890. 



garnetiferous. This is the same schist that is found with the limestone 

 northwest of West Chester (Cope's), as it may be traced almost 

 continuously along the southerly edge of the South (Chester) Valley 

 Hill. 



THE SERPENTINES. 



The serpentines of these areas may be conveniently arranged with 

 reference to the Laurentian axis above referred to. So arranged, ex- 

 cept the first, and in a general direction from northeast to southwest 

 they are as follows : 



A. The serpentine and steatite of the southeast slope of Chestnut 

 Hill (Laurentian) north of Easton, Pennsylvania. 



B. The great Radnor belt, lying on the northwest of the Lauren- 

 tian, including the belt north of West Chester, with which it 

 is apparently identical and almost continuous. 



C. The La Fayette belt, lying on the southeast of the Laurentian, 

 including the outcrops from northeast of the Schuylkill, south- 

 westward through Lower Merion, southerly Radnor, south- 

 easterly Newtown and the southwestwardly part of Marple 

 township, and the outcrop at Blue Hill. 



D. The outcrop, in the western part of Newtown township, and in 

 the easterly part of Edgemont, including Castle Rock. 



E. The outcrops at Willistown, Chester county, extending a short 

 distance into the northerly part of Edgemont, Delaware county. 



F. The soapstone quarry, or steatite belt extending from Chestnut 

 Hill, Philadelphia, to a point about three-quarters of a mile north- 

 east of Bryn Mawr nearly parallel to, and about a half mile 

 southeast of, the LaFayette belt (C). 



G. The northerly Radnor belt, nearly parallel to the northeasterly 

 part of the great Radnor belt (B) and about a thousand feet 

 northwest of it. 



H. The outcrop on the Wissahickon near the mouth of Cresheim 

 creek, southeast of Chestnut Hill, and certain small areas in 

 Marple and Upper Providence, southwest of the lai'ge Marple 

 outcrop. 



I. The numerous adjacent outcrops in Middletown Township west 

 of Media. 



K. Certain small areas south and southwest of the Media outcrop, 

 and the outcrops near Glen Mills on Chester creek. 



These serpentines have been studied by many geologists but the 

 conclusions reached have not been uniform. The following extracts 



