6 14 APPENDIX. 



was formed, it is necessary, fully to elucidate this matter, trt 

 know that the mountain of Sainte Lucic is generally com- 

 posed of a greyish granite, consisting of quartz, felspar, and 

 mica; and that it has an elevation of about GOO feet *. 



Let us suppose the observer to be placed on the summit of 

 the mountain, where blocks and masses of grey granite lie 

 bare, some of them saliant and affected in a slight degree by 

 timej from this point he is presumed to take his departure, 

 as if he would descend by the side of the mountain which ap- 

 parently slopes towards the village of Sainte Lucic. 



His way then lies over the same kind of granitic rock until 

 160 feet below the summit whence he departed, measuring 

 perpendicularly ; in the rock he passes over there is nothing 

 but quartz, felspar, and mica without hornblende. When 

 at this distance below the summit he will notice a change in 

 the rock, which insensibly passes to the state of hornblende 

 rock of rather a greenish black colour, mixed with much 

 White felspar, compact, but in a slight degree granulated, 

 and somewhat similar to antique black and white granite of 

 a fine grain. 



As the observer advances over this differing space he will 

 begin to perceive the first attempts at globular crystallisation 

 in the solid rock; shortly after he will discover a pretty 

 large mass, harder than the mother rock, which rises to a 

 certain height, but at its base adheres to the hornblende 

 rock below. This first block presents globules of different 

 sizes, the spherical form of which is advanced to a more per- 

 fect and regular state than in the crystallisations previously 

 , noticed. 



Finally, at but little distance from this first mass of globu- 



* These instructive details I liave from M. Mathieu himself, whom I had 

 the pleasure of seeing at Paris, on his way to Holland, whither he was going bjf 

 order of the minister. He was kind enough to communicate to me the position 

 of the mountain of Sainte Lucie, to draw a sketch of it, and to mark the places 

 where the globular granite is situate; and at his request it is, and with his per- 

 mission, that I publish this account, to serve as a supplement to what I have 

 vsaid of the orbicular granite of the plain of Taravo. 



