296 Von Hoff on the Origin of Meteoric Stones. 



of stones, between the occurrence of the phenomenon oflight and 

 clouds, and the hearing the report. 



AJifth circumstance deserves particular consideration. The 

 meteoric stones and masses of iron which are found on the earth 

 after the occurrence of the phenomenon, are remarkably small 

 masses in comparison with the size of the fire-balls which have 

 produced them, and which, at a great height above the earth, 

 appear very much larger than they could appear, if the fallen 

 masses had at that height only the same dimensions which they 

 possess when found on the earth, and if they had exhibited their 

 luminous appearance only from an elevation of temperature, or 

 from their being red hot. The difference between the size of 

 the fire-balls and that of the solid masses which have fallen from 

 them, amounts to perhaps a hundred thousand times. 



Sixthly, An amorphous, dull mass of light, occupying, 

 however, greater space than the ball itself, sometimes pre- 

 cedes the formation of a round fire-ball, as when occasion- 

 ally a luminous cloud presents itself, or parallel stripes are seen 

 in the heavens, which afterwards are blended together in a fire- 

 ball. 



All these parts of the phenomenon, viz. the momentary 

 explosion, as well as the temporary display of light, together 

 with the last mentioned phenomena which precede, and pre- 

 pare for the principal occurrence ; further, and chiefly, the con- 

 siderable difference in size between the fire-ball and its product 

 which falls to the earth, cannot be explained by the passage of 

 a solid body through the space above and in the atmosphere. 

 At the foundation of all these phenomena, there must be a pecu- 

 liar, instantaneously-effected, physico-chemical process, regard- 

 ing whose exact nature all the observations hitherto made 

 leave us still in the dark ; hence it seems too soon to endea- 

 vour to explain it by the laws of nature, which have become 

 known to us, or which we think we have ascertained to exist. 



But there is one conjecture which seems to me perfectly natu- 

 ral, and which it is necessary to bring forward, viz. that, at the 

 time when the explosion and evolution oflight occur in a falling 

 meteor, a great chemico -physical operation takes place, which is 

 not merely the accompaniment of the fall of a solid body, or the 

 effect of that fall, but which forms a new body from the original 



