On the Fall of Stones from the Clouds, 259 



^ourid substances which organic bodies, stagnant waters, and all 

 bodies while under decomposition, exhale without ceasing, and 

 which are lost in the air without our knowing any thing as to 

 what they become. It is therefore fair to inquire what are the 

 methods resorted to by nature to counterbalance this perpetual 

 evaporation, and to purify the atmosphere frop all these volati- 

 lized substances. In fact, it is probable that nature employs 

 other methods of purifying the air, and probably the organic 

 bodies are the most powerful to which she resorts. The plants 

 in particular seem intrusted with this office : it seems even that 

 they absorb mucilaginous substances, which, as demonstrated by 

 ftlessrs. Dupuytren, Thenard, and Moscati, exist in great abund- 

 ance in the air. Vegetables feed upon it; and this cause, with 

 several others, makes us conceive how it is possible that plants 

 when jiut into substances incapable of furnishing their alimentary 

 juices nevertlieless grow and vegetate. 



Such are the principal proofs, or rather the most constant 

 facts, which render probable the hypothesis of aerolites being 

 formed in our atmosphere. We may even go the length of 

 saving that these proofs are strong enough to entitle the matter 

 to' be still further investigated : and we are far from thinking with 

 M. Bigot de Morogues in his recent book, that it is rash to con- 

 sider this supposition as probable. We confess with equal 

 frankness, that the hvpothesis of which we have given an account 

 is liable to many and strong objections * ; but is it clearly de- 

 monstrated, as M. Bigot de Morogues advances perhaps too 

 gratuitously, that aerolites have once been small celestial bodies ? 

 If this opinion, which has been hazarded by the most eminent 

 geometricians, was demonstrated, certainly it would be absurd 

 to come forward with suppositions to explain a fact so well as- 

 certained. We do not think, however, we have fallen into an 

 absurdity of this kind ; for in all the explanations hitherto given 

 of the most singular phaenomena, there never was the slightest 

 evidence which follows a demonstration. 



What we have said of M. Bigot de Morogues does not impugn 

 the general usefulness of his work, which is besides the most 

 recent we have on the subject of ayrolites. We could have 



* One of the strongest objections to tlie hypothesis of tlie formation of 

 sciolites in the terrestrial regions is the total absence of oxygen in the stone 

 which fell at Lissa, and whicii has been analysed by Klaproth. It is in face 

 ejiii^uliir, that the molecules of iron and martial pyrites should have re- 

 «ist<d a iburt intlaiHination without bcginoinif to oxidate. But in other 

 .icrolites, like that which fell at Alais, the charcoal which they contain 

 bu.'ns iustuiitly, and tlie silex obtained fisrn it docs not go into a jelly as 

 )ti other inetc'oroliief ; whi'-h proves that tlx y have not undergone a great, 

 degree of hi-at. This last fact is not very favourable to the idea oi' nisro- 

 lites b«iiij;^ durtsd from volciiuoes in the moon. 



R 2 wished 



