376 VICTORIA METEORIC IRON. 



last-named minerals having part of the magnesia replaced by 

 lime. It is identical with the enstatite of Kenngott, a pyroxenic 

 mineral from Aloysthal in Moravia. 



From these observations it will be seen that the Bishopville 

 meteoric stone, however different in external characteristics 

 from other similar bodies, is after all identical with the great 

 family of pyroxenic meteoric stones. 



Enstatite. 



This form of pyroxene was first noticed by Kenngott as a 



new species, in a communication made by him to the Yienna 



Academy in 1855 (see Vien. Acad. Ber., xvi, p. 162; Jahres- 



bericht for 1855, page 928). Its composition there given is 



Silica 57.09 



Alumina and oxide iron 5.13 



Magnesia 35.85 



Water , 1.92 



99.99 

 As the crystallographic character of this mineral entitles it to 

 separation from pyroxene, or, in other words, as it is entitled to 

 be ranked as a new species, the prior right of discovery belongs 

 to Prof. Shepard, and the name first given by him, chladnite, 

 has the priority; but as it has for so long time borne the name 

 of enstatite among mineralogists, any attempt to change it 

 would only bring confusion. This is the more to be regretted 

 since the name of chladni would be a most appropriate affix to 

 a mineral, the true and pure type of which is so pre-eminently 

 that in meteorites. 



In this connection I would refer to the simple chemical rela- 

 tion of three of the most characteristic minerals of meteoric 

 stones ; these minerals forming at least ninety per cent, of the 

 earthy minerals in the aggregate mass of all meteoric stones. 

 The three minerals are: 



Enstatite, R Si Mg Si 



Bronzite, R Si (Mg Fe) Si 



Chrysolite, R 2 Si (Mg Fe)% 



In these minerals the protoxide of iron replaces but a small 

 portion of the magnesia in the last two; so they are virtually 

 silicates of magnesia, containing one or two atoms of silica with 

 one atom of magnesia. 



