42 On Aeroliles. 



gregations of iron, nickel and chromium, with silica, alumina and 

 magnesia; and occasionally sulphur, lime and carbon, more rarely 

 containing traces of cobalt. As for the possibility of the creation 

 of iron, &;c. from simpler forms of matter, vviiich Mr. Brande 

 also presumes, thougli supposititiously, I need only again repeat 

 that we are at liberty to suppose what we will. In presuming my 

 opinion in opposition to that of Professor Brande I shall not be so 

 extravagant, but deduce what I may consider fair data from the 

 history of meteorolites, and the circumstances which announce 

 and accompany their fall. 



I think it evident that these meteoric bodies are not wander- 

 ing masses circulating round our globe, nor chips from any planet 

 moving within the compass of the solar system. But I will not 

 say either that they are the gifts of our atmosphere, or extra- 

 atmospheric, and formed on the surface of its outer shell. 



It is surely more reasonable to suppose that they spring from 

 the thunder-storm, than that the storm is the result of their ac- 

 tion. 



They do not penetrate far into the earth ; sometimes are sim- 

 ply scattered on its surface. Now, if the elevation at which they 

 were formed was very considerable ; on the well-known laws of 

 gravitation, thev should sink deep into the soil. 



Though tlie peculiar proportional associations are not disco- 

 verable in any terrestrial mineral, still the substances themselves 

 are not rare in tlie earth. 



As to the agency which carried thenti to such lofty elevations, 

 1 cannot find it either in volcanic forces or the whirlwind from 

 the desert; nor do I discover in volcanic products materials for 

 their construction. 



Hydrogen variously combined is continually escaping from all 

 parts of the surface of the globe; sometimes it carries on its wing' 

 iron or carbon or sulphur or other materials; and who shall decide 

 that nickel in intimate chemical combination with iron, or si- 

 lica witii oxide of iron, &c. may not be transported in such a ve- 

 hicle ? And the combined hydrogen might in virtue of its great 

 levity, and expanding as it ascended, finally brave the outer circle 

 of the atmosphere and settle upon its waves. — We have no right 

 to limit its solvent powers, and it is still questionable whether it 

 has ever yet appea-ed to the chemist in a simple form. We know 

 it dissolves iron, zinc, arsenic, tellurium, selenium, potassium, 

 boron, carbon, sulphur, and phosphorus ; and we have no autlio- 

 rity to restrict its powers to even these. As for oxygen*, &c. — for 

 any thing I know they may have very exalted solvent powers. 



We have then only to suppose two immense aerial volumes 



• Professor Giabert of Turin told me he had found invariably, that oxy- 

 gen obtained from pci oxide of mercury, when respired, produced salivation. 



loaded 



