SERPENTINE. 201 



serpentine is not less remarkable than the other pecu- 

 liarities of the latter roek ; and is farther indicated by 

 the frequent occurrences of steatite in the traps, and 

 of hornblende in the Serpentines. 



Some observations long posterior to my own, have 

 not only confirmed them, but proved what I then sug- 

 gested, that veins of Serpentine alone might exist, 

 since that substance formed portions of trap veins. 

 Mazzari has found such veins in the alpine limestone 

 of the country of the Avisio; while Parolini and 

 Webb have observed basalts and amygdaloids con- 

 taining steatite, then becoming serpentine, and lastly 

 sending veins of this substance into the mountain called 

 the Giants' bed, on the Bosphorus. The transition of 

 trap into Serpentine occurs also at Predazzo in the 

 Tyrol, in the same manner as at Clunie; and it is re- 

 markable that where the veins occur at Santa Pe in 

 the Pyrenees, they consist indifferently of hornblende 

 rock, basalt, and serpentine. In South America, at 

 Venezuela, serpentine and greenstone are said to al- 

 ternate. According to Cordier, the basalts of the Bos- 

 phorus are of volcanic origin; but whether this be 

 the fact or not, the existence of volcanic serpentine in 

 the form of veins seems established; as an amygdaloi- 

 dal rock in the volcanic mountain Akkrefell in Ice- 

 land, is traversed by such veins, of four feet in thick- 

 ness. I must add to these important facts, that the 

 transition between granite and serpentine, which I ori- 

 ginally observed in Aberdeenshire, is now spoken of 

 by Mazzari as unquestionable. 



Here, then, Serpentine displays all the characters of 

 an unstratified and venous rock, of igneous origin. 

 The evidence seems as complete as it can well be; and 

 if it does not receive some additional support from 

 another analogy, that may at least remove an objection 



