in the Jppenines of Liguria. 305 



This fine specimen is five inches \oug by three bl-oad ; one 

 of its facets presents the whole characters of a fine green 

 variohte, with small grains projecting a little, and of a green 

 much clearer than the heart of the stone, while the opposite 

 part is a true serpentine of a dark green, without globules 

 or variolitic spots* We could not doubt, after looking at 

 this specimen, that the substance which was joined in glo^ 

 bules in order to form this variolite, was the result of an as* 

 semblage of a certain quantity of feldsparry substance, the 

 elementsof which had been mixed in the serpentine rock at the 

 time of its formation. This kind of separation may be con- 

 sidered as the result of a globulous imperfect crystallization, 

 determined by the attractive force of the feldsparry mok- 

 cules, which had more affinity fcr each other than for the 

 jnagnesian earth J and if these variolitic globules are only 

 superficial as it were, (for the bed m which we remark thera 

 is little more thajn three Unes thick,) it is because the sub- 

 stance of the feldspar was not abundant. In short, the 

 identity of th€ globulous substance is absolutely the same 

 with that which I found, separated and in voluminous pieces, 

 in the bed of the Charavagna, and which I have mentioned 

 in No. IX of the description of stones found in this torrent. 

 In fact, having attacked with the blowpipe son>e globules 

 of the variolite in question, they swelled upon the first at- 

 tack of the d-re, emitted some air bubbles, and formed a 

 yellowish transparent glass, like the fddsparry stone abov<3 

 mentioned. 



A^ variolite equally well characterized,^ in the ucighbour* 

 hood of the rock of which it had once formed a part, gave 

 me good hopes of meeting with some more of them. These 

 hoj^s were soon realised ; for after we had ascended 300 feet 

 higher, we found beneath our feet several flat pieces, but 

 angular, and of hard serpentine of a lighter or darker green 

 fiUed with vK^iolitie globules, the grains of which were 

 much thicker, and penetraitcd into the whole mass of the 

 serpentine. I gathered several fi;;e specimens, some of which 

 are six or eight inches loi^ by^n inch in thickness, and of 

 so decided a character that we eaa easily distinguish with 



Vol. 30. No. IftO. May 1 808. U the 



