130 DOMAIN I. SIDEROUS. 



last only appears in the form of rocks. Saussure, 

 who calls it delphinite, or green schorl of Dau- 

 phiny, describes a rock of this kind. He also 

 mentions smaller portions of a compact kind. 



That the glassy actinote strictly belongs to the 

 siderous domain, will appear by the analysis of 

 Vauquelin; silex 37, argil 21, lime 15, oxyd of 

 iron 24, with a small portion of manganese*. 



Texture, sometimes massive, but generally in 

 thin six-sided acicular crystals. 



Hardness, between marmoric and basaltic. 

 Fracture, fibrous and radiated. Fragments, splin- 

 tery and very sharp. 



Weight, siderose. 



Lustre, shining and glassy; strongly translu- 

 cent. 



Actinote, from Switzerland, where, as has been 

 mentioned, it forms entire rocks. 



STRUCTURE III. SIDEROUS SERPENTINE. 



Of this kind Humboldt discovered a curious 

 rock with magnetic power, forming the mountain 

 of Regelberg, in Germany; the south side attract- 



* Lametherie observes, that the earthy smell shows an approxi- 

 mation to hornblende. Th. de la Terre, ii. 373. Is not schorl a 

 black actinote? 





