1 20 OOPMOS. 



contain, for instance, crystalline substances, perfectly similar 

 to those of our earth's crust ; and in the Siberian mass of 

 meteoric iron investigated by Pallas, the olivine only differr. 

 from common olivine by the absence of nickel, which is re- 

 placed by oxide of tin. * As meteoric olivine, like our basalt, 

 contains from 47 to 49 per cent, of magnesia, constituting, 

 according to Berzelius, almost the half of the earthy com- 

 ponents of meteoric stones, we cannot be surprised at the 

 great quantity of silicate of magnesia found in these cosmica 

 bodies. If the aerolite of Juvenas contain separable crystals 

 of augite and labradorite, the numerical relation of the consti- 

 tuents renders it at least probable, that the meteoric masses 

 of Chateau- llenard may be a compound of diorite, consisting 

 of hornblende and albite, and those of Blansko and Chanton- 

 nay compounds of hornblende and labradorite. The proofs oi 

 the telluric and atmospheric origin of aerolites, which it is 

 attempted to base upon the oryctognostic analogies presented 

 by these bodies, do not appear to me to possess any great 

 weight. 



Recalling to mind the remarkable interview between New- 

 tori and Conduit at Kensington,f I would ask why the ele- 

 mentary substances that compose one group of cosmical bodies, 

 or one planetary system, may not in a great measure be iden- 

 tical ? Why should we not adopt this view, since we may 

 conjecture that these planetary bodies, like all the larger or 

 smaller agglomerated masses revolving round the sun, have 

 been thrown off from the once far more expanded solar atmo- 

 sphere, and been formed from vaporous rings describing their 

 orbits round the central body ? We are not, it appears to 

 me, more justified in applying the term telluric to the nickel 

 and iron, the olivine and pyroxene (augite), found in meteoric 

 stones, than in indicating the German plants which I found 

 beyond the Obi as European species of the flora of Northern 

 Asia. If the elementary substances composing a group of 

 cosmical bodies of different magnitudes be identical, why 



* Ber/elius, Jaliresber., bd. xv. a. 217 und 231. Rammelsberg, Hand- 

 worterb., abth. ii. s. 25-28. 



f " Sir Isaac Newton said he took all the planets to be composed ol 

 the same matter with the Earth, viz., earth, water, and stone, but vari- 

 ously concocted." Turner, Collections for the History of Granthan^ 

 containing authentic Memoirs of Sir Isaac Newton, p. 172. 



