340 On Hypotheses proposed for explaining 



flight to the earth." Now, according to his own statement, the 

 gases could never he ignited : for if the hydrogen and oxygen 

 gases were in separate volumes, the passage of the electric spark 

 from one to the other could inflame neither, each being incapable 

 of ignition when alone; and if they were either mixed or in con- 

 tact, no electric spark could be exhibited, as the electric fluid 

 would theij pass silently from one to the other, and consequently 

 there could be nothing to inflame the mixture ; so that this alone 

 would be sufficient to overturn the hypothesis. 



But let us again have recourse to our liberty of making what 

 suppositions we please, and suppose that the gases would really 

 be ignited: does it from tbence necessarily follow that the stony 

 materials must undergo fusion? or, if they do, that they must 

 therefore be aggregated into one solid mass? These are certainly 

 far from being self-evident consequences ; so far, indeed, that 

 they appear altogether improbable : for instance, if sulphuretted 

 hvdrogen and oxygen gases be brought into contact and inflamed, 

 so long as the quantity of the latter is either considerably less 

 than that of the former, or supplied slowly, a great portion of 

 the sulpliur will be deposited, unchanged, in the form of a fine 

 diffused powder. And if such an inflammable body as sulphur be 

 not ignited, how very improbable it is, that such stubborn ma- 

 terials as iron, alumine, and silica should undergo fusion ! Should 

 it, however, be alleged that the sulphur is actually fused in this 

 experim.ent, but, on account of the greater affinity of hydrogen 

 for oxygen, it could not become ignited for want of the latter; it 

 must then undoubtedly follow, that fusion does not necessarily 

 lead to ih.e aggregation of the different parts even of the same 

 substance, much less then of heterogeneous materials. Hence 

 it is very improbable that the stony or metallic parts would un- 

 dergo fusion; and even if they did, it would be altogether in- 

 adequate to account for the aggregation of such different mate- 

 rials into one mass: for we know that all chemical depositions 

 from the explosion of gases are in the form of fine powders. 



One circumstance attending the fall of meteoric stones seems 

 to have been overlooked not only by Mr. IVI. but by almost every 

 one who contends for their atmospherical origin ; and yet it is a 

 difficulty of no common magnitude ; — indeed the obliquity with 

 which thev fall seems altogether unaccountable on any known 

 principles, if they be generated in the atmosphere. The electric 

 fluid has by some been supposed to be the moving jjower in this 

 case ; but it appears to be incapable of commuuicating such a ve- 

 locity. In the most tremendous thunder-storms it never removes 

 any thing from its place more than a few yards ; it therefore can- 

 not be this power whicli communicates their horizontal velocity to 



meteoric 



