of Serpentine, SfC. in the Apennines. 181 



the various matter carried up by these vapours, I presume 

 that they originate beneath this limestone, and that conse* 

 quently the newest rock in which the focus of these pheno- 

 mena can be placed, would belong so the transition forma- 

 tion. 



Monte Ramazzo, a mountain on the N.W. of Genoa^ 

 which is a continuation of that of Guardia, is composed of 

 diallage serpentine, containing copper pyrites, and gives rise 

 to works of sulphate of magnesia, described by Messrs. 

 Faujas, Moyon, Viviani, Cordier, «&c. of amygdaloid ser- 

 pentine, rare, certainly, but perfectly resembling that of 

 Pietramala, and of calcareous schist (calschiste) passing into 

 steaschist. The formation on which the serpentine is placed, 

 is here different from the calcareo-sandstone formation that 

 I have observed in the places cited above. It appears to 

 be wanting, and the serpentine is placed immediately upon 

 a transition, and perhaps even primordial calcareo-talcose 

 formation, very different from the preceding. It possesses 

 all the characters of ancient rocks ; the limestone is almost 

 lamellar ; it is mixed in thin, tortuous beds ; and is as it 

 were dissolved with the shining slate and steaschist ; but 

 the serpentine is not covered by any other rock, conse- 

 quently nothing shews it to be inferior io the rocks that I 

 have referred to the Alpine formation.* 



Dialiage serpentine also occurs at the pass of the Bochetta, 

 and which, situated on the north of Genoa, forms part of 

 the crest of the Apennines, in this portion of Liguria. It is 

 tery difficult to observe its position : it appears to be the 



* M. Faujas (Annales du Museum, t. viii. p. 313), states, that in tlia 

 torrent of Charavagne, serpentine is seen united to limestone by veins of 

 spathose carbonate of lime, and he has remarked the amygdaloidal dial- 

 lage rock (euphotide variolitique) which he describes by the name of 

 Variolite a base de serpentine. 



M. Holland (Annales de Chimie et de Physique, t. iv. p. 427,) has 

 also given a description of this mountain, and of the manufacture of sul- 

 phate of magnesia there established. He states that primitive schist i^ 

 undoubtedly the base of the serpentine formation, which rests on it iu 

 considerable mass, and in an unconformable position. 



