DOMAIN I. SIDEROUS. 



are, in like manner, found upon the summits of 

 hills, quite detached from the original beds to 

 which they would seem to belong by the identity 

 of their substance. From these remarks it must 

 appear to every impartial mind, that the pheno- 

 mena of basalt are on too vast a scale, and of an 

 appearance toTo uncommon, to be produced even 

 by a chain of volcanoes, of which the Andes 

 present most extensive examples; so that to 

 confine the appellation of basalt, with the French 

 mineralogists, exclusively to a pretended com- 

 pact lava, would be a mere assumption, alike 

 foreign to ancient erudition, and the precision of 

 modern science. 



STRUCTURE I. AMORPHOUS BASALT*. 



Egyptian. Basalt of a greyish black, with very small grains 

 of white quartz, and spots of iron ochre, from 



Egyptf. 



Basalt of a blueish grey, glimmering lustre, and 

 fasciculated fracture, from the same. 



* It is always of a mingled aspect. 



f It is only to be inferred that the Egyptian basalts do not belong 

 to the columnar. Ferber erroneously says, that Strabo mentions 

 the Ethiopic basalt as columnar. That author, lib. 17, describes a 

 pyramid, partly built of basalt, from the extreme mountains of 

 Abyssinia. 



