ON GLAüCOPHANE. 93 



step by step, every stage of transformation from diallage to glaucophane, 

 and furthermore to a fibrous asbestiform substance. (Fig. III.) Com- 

 pact glaucophane is comparatively rare, and if it is present then, shows 

 a columnar form terminated at both ends by radiating tufts of the 

 glaucophane-asbestus. 



Both the glaucophane, and glaucophane-asbestus extinguish the 

 light at the same time, and the ray vibrating parallel to C is of a 

 light blue; at ± to it light lavender-blue. Sometimes the asbestus- 

 fibres assume a light yellow colour or become even colourless; this 

 mass alone makes up nearly the whole rock. 



Sometime ago, a stone-ax ( 10 cm. x 2 by 1/3 cm. in size ) was 

 brought from the village Nomiya near Sapporo, Yesso (Hokkaido); 

 this is supposed to have been used by Ainos, the aborigines of that 

 island. A slide made from this possesses exactly the same feature as 

 that of Ivitagawa, and therein we find a few diallage-remnants, one 

 portion of each of them has been already changed into glaucophane, 

 showing, if proved on the extinction-direction, a considerable devia- 

 tion in their angular measurement. 



It elucidates most typically the various stages of fibrillation from 

 the intact diallage to an infinitely small crocidolitic fibres. A resolved 

 part displays a corymbose ramification, proceeding from both ends of 

 diallage-individual, and afterwards it makes undulating curves, indicat- 

 ing the effect of pressure upon the rock. (fig. I.) Farther researches 

 of glaucophane-rocks from other localities might bring forth many not 

 uninteresting fiicts, considered especially from the ethnological point 

 of view. 



(c.) The amphibolite of a serpentinous aspect is most typically 

 developed near Izushi in Kodama Gori, Musashi province. By a 

 macroscopical consideration it looks just like an ordinary blue ser- 

 pentine, for which, indeed, it has often been taken; and in which here 



