Von Hoff on the Origin of Meteoric Stones. 287 



self the merit of having originated the theory of the atmos- 

 pheric origin of meteoric stones. 



The following are the chief arguments adduced by Berzelius 

 in favour of the lunar origin of meteoric stones.* 



1. Meteoric masses contain metallic iron, or are entirely com- 

 posed of it. All iron penetrated by water containing air, be- 

 comes rusted (oxidised) ; and this invariably takes place.on the 

 earth's surface. Metallic iron must therefore come from a place 

 where there is no water ; in the moon, as we must conjecture, 

 there is no water ; there alone, therefore, can iron remain in a 

 metallic (unoxidised) state; consequently meteoric stones may 

 be derived from the moon. 



2. Most meteoric stones are as similar in their constituent 

 parts as if they were derived from one mountain ; only a few 

 have been found with a different composition. On the earth 

 there is a variety of mineral compounds occurring at different 

 places. This may also be the case in other heavenly bodies, 

 and in the moon ; hence we may suppose that various mineral 

 mixtures would come from the moon, if they were derived from 

 different portions of its surface. 



3. Masses ejected by the moon, would most easily reach the 

 earth's surface, when thrown out from the centre (or at least 

 some point near the centre) of the side of the moon turned to- 

 wards our globe. The species of rock which predominates there, 

 would hence afford the largest number of meteoric stones, and 

 thus most of them resemble one another. Ejected masses from 

 other parts of the moon do not proceed in such direct lines to- 

 wards the earth ; hence they more rarely come within the in- 

 fluence of the earth's attraction, and these are probably those 

 stones which have a different composition from the majority. 

 Can perhaps, says Berzelius, the quantity of nickeliferous iron, 



. on this side of the moon, be the cause that the latter always turns 

 the same side to the earth ; owing to the magnetic attractive 

 power of the earth acting chiefly on this side, and less or not at 

 all on the other, which probably contains no nickeliferous iron ? 



4. When we examine meteoric stones as mountain rocks, we 

 find that they are extremely different from those of the earth. 

 The abundance of magnesia, the rarity of silica, and the incon- 



* A more detailed account of the opinion of Berzelius on the origin of me- 

 teoric stones is given in the beginning of this volume of the Journal. 



