DOMAIN XI. DECOMPOSED. 



HYPONOME II. 



Micronome 1. The same, with noble opal, 

 from Czerweniza in Hungary. 



Micronome 2. The same, with black opal, from 

 the same. 



Micronome 3. The same, with milk opal, and 

 many other kinds, from the same*. 



NOME III. D. SLATE. 



Some kinds of slate, especially those mixed 

 with calcareous matter, easily exfoliate and de- 

 compose. 



NOME IV. D. QUARTZ. 



This substance is far from being easily decom- 

 posed; but, from some unexpected intermix- 

 ture, it sometimes though rarely decomposes in 

 granite, while the felspar remains entire. Mr. 

 Kirwan has an article concerning earthy quartz, 



* See Townson's Travels in Hungary, for an ample account of 

 the opal mines. 



