DOMAIN II. SILICEOUS. 



enters into the composition of this granite, ap- 

 pears a little unctuous in its fracture 3 a frag- 

 ment, of the fifteenth of a line long by a thirtieth 

 in thickness, or of 0,067 by 0,033, fixed at the 

 extremity of a thin rod of iron, became perfectly 

 rounded in the flame of the blow-pipe, losing a 

 little of its transparency, which in this piece 

 appeared perfect, and some bubbles rose in its 

 interior. This quartz is therefore more fusible 

 than rock crystal, in the proportion of 0,035 to 

 0,014. 



" These granites are frequently mingled with 

 hornblende, here blackish, there inclining to 

 green. 



" There is also seen chlorite, often of a black- 

 ish green, sometimes in veins, sometimes in nests, 

 and even in pretty thick masses. It is soft, but 

 not friable; of a very fine grain, and its small 

 particles, viewed by the microscope, appear very 

 translucent thin plates, of a bright green ; but 

 they have not the regularity of those of St. 

 Gothard, which I have described in 1893. 

 This fossil, like hornblende, appears to retain in 

 these granites the place of mica, which does not 

 appear in it, except in very small and scarce 

 $pangles. 



" Some of these granites appear curious, there 

 being small cavities of angular and irregular 



