M. Godon’s mineralogical observations. 129 
Definitions and preliminary explanations. 
Primordial soil. J call primordial, that part of the surface of the 
earth, formed of some of those simple or aggregate mineral masses, 
commonly called rocks, which have never been found containing rem: 
nants of organized bodies, and which are supposed to have been pre- 
existent to the formation of animals and vegetables. I take this defi- 
nition in its most extensive sense, without admitting any gradation in 
antiquity, among primordial rocks, for fear of oie my observa- 
tions to some systematic opinion, ~ 
Amapintiolard. fee rock, Hays | cy: i 
oie, pent? " wets So Werner.) — 
ty Spee pation, most ech of amphibole and felspar, admit- 
ting in its composition quartz, epidote, talc, mica, and almost always 
sulphurated iron. Amphibole, which characterises this rock, is sup: 
posed to be the predominant substance. When the felspar is in 
greatest a it takes s the name of felsparoi < Sieg 
P ? 2 
tad 
An aggregation of felspar and amphibole ; ; sometimes of felspar 
quartz, amphibole ; also epidote and mica. When the felspar loses 
its Jaminary aspect, and assumes a compact texture, the rock takes the 
name of petrosilea. 
Petrosilex. (Petrosilex and compact t felspar, Ha: ; ae 
uncertain among other mineralogists. ) 
% “gees 
A rock, homogeneous, or apparently so, of a splintery and semi- 
conchoidal fracture, sparkling most freque tly with steel, and Of aaa 
variety of colours. It often sees small ane popes of <0 . 
: ame 
