234 



while the interior of the mass remained intensely cold. We know 

 that imperfect conductors of heat, when heated to redness, and 

 plunged into cold water, so that they can be momentarily handled, 

 will again become nearly red hot on the surface, by heat derived 

 from the interior. Thus, specimens of lavas, which I collected in the 

 crater of Vesuvius, handled freely, and wrapped up in paper, fre- 

 quently set fire to the paper in a short time after they were so envel- 

 oped. I brought home many specimens which had browned and 

 charred the paper. 



It is also known to all assayers and chemists, that a crucible full of 

 melted flux, if cooled on the surface by plunging the crucible into 

 water, will soon become hot again on the surface, and that the inte- 

 rior of the flux will remain red hot, while the surface of the crucible 

 may be held in the hand for a short time. 



Therefore, mutatis mutandis, there is no inherent improbability that 

 these masses of meteoric stone really would produce the sensation of 

 intense cold, if they were originally cold in the interior, and only 

 rapidly heated on the surface. K the facts are as alleged, this is the 

 first recorded recognition by the human senses of the cold of the inter- 

 planetary regions. It would have been a curious and instructive ex- 

 periment, to have placed one of these stones, soon after it fell, in 

 water, when the formation of a crust of ice on the surface would 

 have visibly demonstrated the fact of intense cold ; and an estimate of 

 the degree of cold could also have been made, by similar means, 

 ascertaining how much the temperature of a given quantity of water 

 was reduced by it, and computing the degrees of cold thereby. 



The weight of the fragment presented to the Society is 4^ ounces. 

 It is 2i inches long, 1| inches wide, and 1 inch in average thickness. 



Its specific gravity is 3.456 at 68° Fah., Barom. 29.9. Its structure 

 is imperfectly granular, but not crystallized, and there are small black 

 specks of the size of a pin's head, and smaller, of malleable meteoric 

 iron, which is readily removed from the crushed stone by the magnet. 

 The color of the mass is ash gray. A portion of the surface is black 

 and is scorified by fusion. 



Its hardness is not superior to that of olivine or massive chrysolite. 

 Chemical analysis shows that its composition is that of a ferruginous 

 olivine. 



One gramme of the stone, crushed in an agate mortar, and acted on 

 by a magnet, yielded 0.43 grm. of meteoric iron, which was malleable. 

 After the removal of this a qualitative analysis was made of the resid- 

 ual powder. Another gramme was also taken, without picking out 

 the metallic iron, and was tested for chlorine and for phosphoric acid. 

 The results of the qualitative analysis were that the stone contains 

 silica, magnesia, a little alumina, oxide of iron, and nickel, a little 



