GEOLOGICAL SOCIETY. 



135 



FOURTH CLASS, FIRST ORDER— SULPHUR. 

 From wax to diamond lustre. 



Mono-axis. Without distinct cleavage in one direction 

 only. 

 H. from 1| to 2§. 

 G. from 1, 9 to 2. 



SECOND ORDER— ROSIN. 



Common lustre. 

 Mono-axis and opaline. 

 H. from 2 to 3f. 



G. from 1 to 1, 6 ; and again, from 2, 1 to 2, 2; 



streak neither black nor brown. 

 Examples — oxalite, honeystone and yellow mi- 

 neral resin or amber. 



THIRD ORDER— BITUMEN. 



Wax lustre. 



Mono-axis, as naphthaline ; opaline, as elastic bitumen ; 

 or liquid, as naphtha. 



H. from 0 to 2. 



G. from 0, 7 to 1, 2. 



Bituminous odor, as petroleum or uncolored 

 streak. 



