4-30 Prof. Berzelius om Meteoric Stones.' 



the opinion of their formation from either the common, or 

 even the accidental constituents ofthe atmosphere be admitted. 

 Anaxagoras imagined that a stone which fell in his time in 

 JEgos Potamos came from another world. This, which is 

 probably a correct opinion, is siipportetl by tlie researches of 

 our own age. Olbers in a paper on the fall of a meteorite 

 which occurretl at Sienna in Italy, on the 16th of July ITg**, 

 suggested, in 1795, the possibility of these bodies being pro- 

 jected from the moon, but it appeared to him much more 

 likely that they came from Vesuvius. Laplace likewise adopted 

 this opinion in 1802. That part ofthe moon which is turned 

 towards us is covered with elevations, and it is found that 

 there are many mountains which precisely resemble in their 

 external appearance those volcanos of our earth which have 

 craters; these mountains are of such magnitude that the in- 

 terior of their craters may be seen with good telescopes; and 

 it can be readily perceived that one halt of the interior is il- 

 luminated by the sun, and the other is in the shade, whilst the 

 circular opening of the crater is extremely distinct. It may 

 then be supposed that these mountains owe their form to the 

 same cause as terrestrial volcanos, viz. to eruptions; but if 

 the force which produces lunar eruptions is as considerable as 

 the projectile force of our volcanos, the bodies thrown out 

 ought to be projected much further from the moon than 

 the earth ; for, 1st, the mass of the moon is to that of 

 the earth only as 1-45 to 100, and its weight is in the same 

 ratio; 2ndly, the moon has no atmosphere, or at most one so 

 highly rarefied that when the fixed stars are eclipsed by the 

 moon, no refraction of the rays of light can be perceived: con- 

 sequently the projection occurs m vacuo, and without that 

 mechanical resistance to projected bodies which is caused by 

 the atmosphere of the earth, in which they soon become qui- 

 escent; 3rdly, if a body is projected towards the earth from the 

 moon the attraction of the earth for it continually increases, 

 whilst that of the moon diminishes more and more; 4thly, the 

 limit of equilibrium between the earth and the moon is much 

 nearer the latter than the former. 



Many circumstances connected with the composition of me- 

 teoric stones agree with what we know respecting the moon. 

 Some of these bodies contain metallic iron, which when ex- 

 posed to air and moisture is by degrees converted into 

 hydrated peroxide of iron, and this is the case with the 

 minerals of the crust of our globe under such circumstances; 

 therefore in their primitive situation they are without atmo- 



* [The full at Sienna in 1/94 was of a number of meteoric stones. — 

 E.W.D.] 



