SYNTHETIC EXPEMMENTS BELATIVK TO METEORITES-APPROXIMATIONS TO 

 WHICH THESE EXPERIMENTS LEAD.* 



BY M. DAUBUEE, MEMBER OF THE INSTITUTE, INSPECTOR GENERAL OF MINES. 



\_Translated for the Smithsonian Institution.'] 



Tlie study of raotoorites touches on several fandaraental questions of the 

 physical history of the universe. Aside from the importance which these bodies 

 pi'esent in a purel}' astronomical point of view, they are furthermore of interest 

 to geoloijy from their constitution itself, and this under a two-fold aspect. On 

 the one hand, they are the only specimens of extra-terrestrial or cosraical bodies 

 with which it is possible for us to have actual contact; or which can aflFord 

 us any ideas respecting the constitution of the bodies scattered through the 

 celestial spaces. On the otlier hand, the more thorough our study of them the 

 better shall wo recognize the bearing which they may have on sundry branches 

 of knowledge, and particularly the history of our globe, as will be seen further 

 on. Thus it is that meteorites c(^nstitutc an essential as well as new chapter in 

 geology ; and notwithstanding the little attention hitherto accorded to their study 

 by geologists, it cannot but be considered, on the grounds just stated, as meriting 

 a place in the pages of the Atmalcs dcs Mines. 



In a recently published report on the progress of a part of geology, which 

 may be called experimental geologi/,i we had occasion to explain how far experi- 

 ment had been made instrumental in solving the questions which relate to the 

 origin of meteorites and the mode of their formation ; this chapter it has been 

 thought proper to reproduce here, Avith some developments, a portion of which 

 had found a place in previous publications. The title sufficiently indicates the 

 pi'opriety of reducing the historical and descriptive part to a very succinct 

 exposition. 



CHAPTER I. 



EXTRA-TEKRESTRIAL ORIGIIV OF METEORITES. — PHENOMENA WHICH ACCOM- 

 PANY THEIR FALL. 



It is a long time since any doubt could be entertained that among the sul)- 

 stances which fall from the atmosphere to the surface of the globe, there are 

 some whose origin is incontestably foreign to the planet which we inhabit. 

 Their descent makes itself known by a considerable production of light and 

 sound which accompanies it, by the almost horizontal trajectory which they 

 describe, and by the excessive velocity of the bolides which embody the sub- 

 stances in question. 



Several recent falls, which have been studied with care, have enabled tis 

 to determine with more precision the circumstances which attend the arrival 



* AnnaUs dcs Mines, Sfc , Faris, 18G8. 



+ liappvrt sur les p?ogrcs (it la geologic expdrimcntale. Imprimerie imp6riale, 1607. 



