NOME I. MIAGITE. 



as already mentioned, will chiefly consist 

 of those that depart in their structure from 

 the common laws of nature. 



NOME I. MIAGITE. 



This rock is generally considered as the most 

 beautiful which has yet been discovered. In 

 the mode it is a granitel, being a mixture of 

 white felspar and black siderite ; whence it has 

 by some been called Corsican granite, or Corsi- 

 can granitel ; and by others, from some resem- 

 blance to the eye, ocular granite, or, as it more 

 properly may be expressed from the Greek, 

 ophthalmite. The structure however forms a Description, 

 complete anomaly from that of granitel, as it 

 consists of concentric but irregular circles of 

 white felspar and black siderite, disposed in 

 broad or narrow lines, which are defined with 

 the greatest precision*. Sometimes one oval 

 spot of the siderite is surrounded by an irregular 

 oval of the felspar ; the base or ground of the 

 whole being siderite and felspar irregularly in- 

 termixed. In other spots the centre of siderite 

 is surrounded by a light grey mixture of the two 



* There is no radiation from the centre, as in the plate of 

 Patrin : that of Besson is preferable. 



