ON THE SO-CALLED CRYSTALLINE SCHISTS OF CHICHIBL". l'2i) 



felspar, formed by the mntujil reaction of both mineralH, the teriiiiiiated 

 ends of epidote-individiuils projecting into tlie substance of felspar, 

 as described by (r. H. Williams. O 



As has been already stated, a typical exposure of the gabbro- 

 diorite is found at Kanasaki near the village of ^linano, along the 

 cliif of the Arakawa. There the rock passes insensibly into serpentine 

 which occurs as dykes in the o-ranhite-sericite-schist ; and the hifrher 

 part of the cliff is entirely covered by a mass of the serpentine. 



The serpentine is of a bluish eolour ; the weathered portion of 

 it may be easily parted in shelly masses. Under the microscope in 

 polarized light, the whole rock appears t<j consist of long, divergent 

 flakes, transmitting a gray or blue light ; in short, it looks just like 

 williamsite from Easton in Pennsylvania, although the presence of the 

 nickel oxide in (jur specimen is not yet proved. Our serpentine may 

 have probably resulted from the decomposition of secondary amphi- 

 boles, and up to the present no traces referable to the structure of the 

 divine-bearing variety has been discerned ; the presence of olivine is, 

 however, not absolutely denied, as it seems to be fjund in other 

 serpentines occurring in the neighbouring districts. 



The serpentine is very frequently met with on the southern side 

 of the Arakawa from Nabeyama-Fuppu to the Kainita pass in a 

 long discontinuous ehain of a dyke, running from S. 20° E. to X.AV. 

 for a distance of 10 km.; and its north-western prolongations may be 

 traced still further at Köchi in the Minaregawa vallev (see Profile III). 

 Its mode of occurrence can be understood clearly by referring to 

 the profiles I and II. 



The serpentine rocks lend a peculiar featiu-e to the topography of 

 this region by their compact texture, and they stand out in promi- 

 nences from the surrounding schists and gneisses. As to its economic 



1) op. cit. )). 31. 



