DOMAIN I. SIDEBOUS. 135 



MODE XVI. SIDEROUS GLUTENITE. 



In arranging these substances, two objects 

 are to be considered ; the nature of the frag- 

 ments or particles cemented, and that of the 

 cement itself. When they are both of one kind, 

 as a siliceous bricia*, or a pudding-stone with a 

 siliceous cement, there can arise no doubt con- 

 cerning their classification : but when, as often 

 happens, the fragments are of one kind, and the 

 cement of another, the domain may appear 

 doubtful. The more general method however 

 appears to have been, to denominate the sub- 

 stances from the cement, as being the pre- 

 dominating agent ; and this rule is particularly 

 applicable in the present instance, as oxyd of 

 iron forms the strongest of natural cements. 

 Bricias of basaltin or jasper are commonly ce- 

 mented by the same substance, and sometimes, 

 though rarely, by quartz ; but they may still be 

 referred to the predominating substance, the 



* This word is strictly Italian ; Iricia, a crumb or small frag- 

 ment, with its derivatives Iricioletta, a little crumb, Iriciolmo, and 

 Iriciolo. Breccia b only a corruption. 



The Italian architects and statuaries gave the first modem classical 

 names to rocks, as granite, granitone, granitino, &c. &c. 



