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Dr. Walter Flight — History of Meteorites. 





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The stone of Aumieres consists of a grey rock, like that forming 

 the meteorite of Aumale (1865, August 2oth), which possesses the 

 remarkable property of turning black when heated. By the friction 

 of such surfaces and the consequent development of heat the adjacent 

 surfaces undergo a true metamorphism, and the grey face as a con- 

 sequence becomes black. The faults in such cases have the form of 

 black lines which have very much the appearance that they would 

 present if traced with a pen. On comparing different fragments it 

 becomes evident that where the throw and as a consequence the 

 mechanical effect have been considerable, the black lines have a more 

 marked character. The thickness indicates the degree of dynamic 

 energy to which the stone has been subjected, and the grey rock 

 of Aumale and Aumieres is in fact an extremely sensitive thermo- 

 meter of a kind that may render great service in the study of the 

 conditions to which meteorites may have been exposed. 



1843, June 29th. — Manegaum, near Eidulabad, Khandeish, India. 1 



The conspicuous ingredient in this stone is a pale yellow-green, or 

 primrose-coloured mineral, with a tint similar to that of a very pale 



oblique fault. It seems, however, that his description is taken from the block and 

 not the engraving, which by his kind permission I have reproduced ; and that the two 

 faults respectively referred to are : one of those on the top towards the right, the 

 other that which appears to connect the two great perpendicular veins. 



1 N. Story-Maskelyne. Philosophical Transactions, 1870, clx. 189. — Proc. Royal 

 Soc, xviii. 146. For an earlier notice see Phil. Mag., 1863, xxv. 39, and Journ. Asiat. 

 Soc. Bengal, xiii. 880. (The date formerly assigned to the fall of this meteorite, viz. 

 the 16th July has been shown by General Cunningham to be erroneous.) See also 

 C. Eammelsberg. Die Chemische Natur der Meteoriten. Abhandlungen Ah. Wiss. 

 Berlin, 1870, 120. 



