GEOLOGICAL SOCIETY. 



121 



Soluble on the tongue, without salty, alkaline and 

 sweet taste. 



When H. i to 4, and G . from 1, 8 to 7, 4, they 

 belong here under the following condi- 

 tions : 



If G. less than 2, 1, and they are opaline, and 

 not easily electric by friction. 



If G. from 2, 1, to 3, 4, and they are not black 

 with black streak, nor yellow with yellow 

 streak. 



If G. from 3, 5 to 7, 4, and they have distinct 

 cleavage, with blue, green and white 

 streak ; only when G from 5, 7 to 6, and 

 they have reddish yellow streak. 



When H. from 4 to 5f , and they are not red 

 with red or yellow streak, neither yel- 

 low, brown or black, with yellow, 

 or black brown or black brown 

 streak ; moreover without distinct 

 dodocahedral cleavage. 



When H. from 5| to 8|, and G. from 2 to 4, 

 except such as have G. 3, 5 and more, 

 give a black, deep brown or yellow 

 streak, and those which by rhombic 

 cleavage give a yellowish gray streak. 



When H. from 7 to 8 and less, and they are te- 

 tragonal or pyramidal. 



Vol. I— Q 



