NOME VII. VOLCANIC INTRITE. 



may be regarded as fragments of a primitive 

 rock, ejected without having undergone the action 

 of volcanic fire*. Leucites are often conjoined with 

 felspar and augite ; and, like topaz, the earth of 

 leucite may occur uncrystallised. 



HYPONOME II. LAVA WITH CALCAREOUS SPAR. 



According to Ferrara, calcareous spar abounds Ferrara's 



, . . r x-,. ., account. 



m the ancient or rather primeval lavas ot iSicily. 

 Though the doctrine of infiltration begins to yield 

 to that of contemporaneous sublimation by heat, 

 yet his arguments in favour of the former have 

 great weight ; for when he afterwards mentions 

 the zeolites found in the same basaltins, and the 

 analcimes of Haiiy, (which he proposes to call cy- 

 clopites, because they were first found in the rocks 

 of the Cyclops, and appeared about the middle of 

 last century in the cabinets of Prince Biscari, and 

 of the Benedictine monastery,) he observes, that 

 ' this substance has not only infiltrated and crys- infiltrated. 

 talised in the most interior recesses of these enor- 

 mous masses of the hard lava, but in a great 

 quantity in the slits and in the middle of the marl, 

 which forms a stratum above all these lavas ; a 

 convincing proof that its origin is posterior to the 

 liquid state of the lava, and foreign to that sub- 



* TWd.ii.-6. 



2 K S 



