jtit Account of a Meteor, 159- 



V. The Crust. 



^ The black external crust adheres so closely to the 

 earthy matter within, that it is not easy to separate it. 

 Indeed, it appeared scarcely worth while to subject it to 

 a. separate analysis, since the blow-pipe sufficiently indi- 

 cates the difference between it and the rest of the stone. 

 For, on heating any small portion of the stone with the 

 most intense flame that the blow-pipe can give, it be- 

 comes covered with a black crust similar to that of the 

 stone. The only point then in which the crust differs 

 from the rest of the stone is, timt it has been changed by 

 strong ignition^ having-^ suffered a sort of vitrification, 

 and its metallic parts a partial oxidizement ; I say, par- 

 tial, for when detached, it is attractable by the magnet, 

 and the file discovers points of malleable iron. 



"VI. The globular bodies. 



These appear to be merely portions of the stone, em- 

 bracing probably all its principles, which have been, 

 melted by intense heat, and, being surrounded by solid 

 matter, have become more or less globular, like the glo- 

 bules of metal which appear dispersed through a flux, in 

 a crucible, after an operation witli a very high degree of 

 heat, upon a very refractory metal. 



The globular bodies in this stone, although not at- 

 tractable by the magnet, readily become so by being 

 heated with the blow-pipe. 



Is the iron in them too highly oxidized to admit of 

 attraction, and, are they partially reduced by ignition oii 

 charcoal?- --Finally, is there not reason to conclude, that 

 these meteoric stones originally presented nothing dis- 

 tinguishable by the eye, except pyrites, and the envelop- 

 ing eiuthy matrix- --that, by the operation of heat, the 

 irregular black masses have been produced, by a partial 

 decomposition of the pja ites— that, by a stili more in- 

 tense heat in certain parts, the pyrites have been altoge- 

 ther decomposed, and malleable iron produced— -that 

 the crust is produced by a mere oxigenizement and vi- 

 trification- --that the difference of colour in the earthy 

 part is owing to the unequal operation of heat, the py- 

 rites being left, in some places, especially in the white 



