£24 COSMOS. 



again (to judge from the proportions cf tho ingredients), ara 

 aggregates of hornblende and albite (Chateau-Renard), or of 

 hornblende and labrador (Blansko and Chantonnay). 



According to the general summary of results given by a 

 sagacious chemist, Professor E,ammelsberg, who has recently 

 occupied himself uninterruptedly, and as actively as success- 

 fully, with the analysis of aerolites and their composition from 

 simple min^rals, " the separation of the masses fallen from 

 the air into meteoric iron and meteoric stones is not to be 

 admitted in its strictest sense. Meteoric iron is sometimes 

 found; though seldom, with silicates intermixed (the Siberian 

 mass weighed again by Heis of 1270 Russian pounds, with 

 grains of olivin), and, on the other hand, many meteoric stones 

 contain metallic iron. 



"A. The meteoric iron, whose fall it has been possible to 

 observe only a few times (Hradschrina, near Agram, on the 

 26th of May, 1751, Braunau, 14th of July, 1847), while most 

 analogous masses have already laid long upon the surfa:'e of 

 the earth, possesses in general very similar physical and chem- 

 ical properties. It almost always contains sulphuret of iron 

 mixed with it in finer or coarser particles, which, however, 

 do not appear to be either iron pyrites or magnetic pyrites, 

 but a sulphuret of iron, ^ The principal mass of such a me- 

 teoric iron is also not pure metal, but consists of an alloij of 

 iron and nickel, so that this constant presence of nickel (on 

 the average 10 per cent., sometimes rather more, sometimes 

 rather less) serves justly as an especial criterion for the me- 

 teoric mature of the whole mass. It is only an alloy of tivo 

 isomorjihous metals, not a combination in definite proportions. 

 There are also present in minute quantity, cobalt, manganese, 

 magnesium, copper, and carbon. The last-mentioned sub 

 stance is partly mixed mechanically, as difficultly combusti- 

 ble graphite ; partly in chemical combination with iron, and 

 therefore analogous to many kinds of bar-iron. The princi- 

 pal mass of the meteoric iron contains also always a peculiar 

 combination of j^li^osjohorus ivith iron and nickel, which, on 

 the solution of the iron in hydrochloric acid, remains in the 

 form of silver-white, microscopic, crystalline needles and lam 



"B. The meteoric stones, properly so called, it is customary 

 to divide into tico classes, according to their external appeal'* 

 ance. The stones of one class present, in an apparently ho 

 mogencous mass, grains and splinters o{ meteoric iro?i, which 



* Ramnielsberg, in Poggeudorff, Annalen, vol. Ixxiv., 1849, p. Ii2 



