NOTES OX THE BATH FURNACE AEROLITE. 107 



though carbonaceous, did not have its interior in the least affected. 

 The heat of meteorites at moment of fall has ever been greatly 

 exaggerated in common narration. It is a most frequent thing to 

 have a record of their being too hot to handle even several hours 

 after the fall. An examination of meteorite literature in the publi- 

 cations of the past century has shown me but two cases among the 

 irons — Agram and Mazapil — where a heat making it difficult to 

 handle the mass at time of falling has been recorded; and in but 

 two cases that I have found in the description of nearly two hundred 

 aerolites has any claim to more than simple warmth at time of fall 

 been made. One might expect this from an aerolite of very loose 

 texture, which would allow rapid penetration of the heat enveloping 

 it when in air; or from an iron with its more ready conductivity. 

 With trivial exceptions these accounts of hot meteorites belong to 

 sensational newspaper stories. There has certainly been heat in 

 melting intensity on the outer surface of the mass, but it has been 

 kept from penetrating by the intense cold of the interior. The 

 W'idmannstaten figures of irons would have been destroyed by 

 intense heat. Cohen explains in this way the change of N'Gourey- 

 ma siderite from an octahedral iron to an ataxite. 



There remains to be noticed the breaking up of the stone in the 

 air. Everything, astronomical inductions as well as physical facts, 

 certifies to the greatly varied size of the cosmic fragments which 

 enter our atmosphere. These variations doubtless existed primarily. 

 But while still in space, circulating in cometary orbits of long 

 extent, there must have been many collisions both among mem- 

 bers of the same stream and with those of other streams, and prob- 

 ably, too. with some of the streams coming, as has already been 

 noted, from opposite directions with opposite course around the 

 sun. Darwin (Geo. II.) has graphically described these streams as 

 hastening ever onward with the same profuse variety of fragments, 

 — great boulders, smaller ones like cobblestones, pebbles, gravel, 

 and even sand — as may be collected at the foot of a rocky cliff. 

 When such a stream chances to come within our earth's attraction 

 and fall into our atmosphere, friction commences with ensuing at- 

 trition, heat, and luminosity. The myriad finer particles are prompt- 

 ly reduced to such comminution that they henceforth fall slowly, 

 reaching our earth with imperceptible fall as cosmic dust. The 

 smaller fragments flash out as shooting stars, none of which, says 



