■ Prof. Maskelyne and Dr. Lang's Miner alogical Notes. 451 



Odessa, and that their anxiety on behalf of the authenticity of 

 the specimen in the British Museum is set at rest. 



1 8 . Plesko witz A ero lite . 



Mr. Greg does not confine himself in his paper of January 

 last to his programme, which included only specimens "with 

 which he has happened to have had to do at various times." He 

 enters also on the discussion of two stones with which he had but 

 a slight acquaintance. One of these was the stone of Pleskowitz. 



The British Museum has the good fortune to possess a speci- 

 men of this fall. The indefatigable researches of M. Kesselmeyer 

 have brought to light the fact that specimens of it were preserved 

 at Prague, as he has also traced the history of a specimen of the 

 Tabor fall into the collection of Colonel Greville, a collection 

 that became the property of the British Museum in 1810. But 

 the original specimens of the Pleskowitz and Liboschitz fall 

 appear to have disappeared from notice at Prague; and it is dif- 

 ficult at present to ascertain how Heuland, from whom this 

 specimen was purchased, became possessed of it. 



That he attached a very high value to it and appreciated its 

 true character is evident from the terms in which he describes it 

 in the original invoice, and indeed also from the price paid for 

 it ; these terms are as follows : — 



"Meteoric stone (weight 1^ oz.) from Reichstadt, Bohemia; 

 fell the 2nd of June, 1823, and is the only specimen seen by 

 Mr. Heuland from that locality. It is surrounded by its crust, 

 and both surfaces show an unusually compact character ; it is 

 mixed with brown oxide of iron. j64." 



Were there any cause to doubt the honesty or the accuracy of 

 this description of Mr. Heuland' s, it would probably be founded 

 upon the external similarity of the falls of Pleskowitz and Tabor. 



It was on this similarity that Mr. Greg founded his own doubt. 

 But in point of fact this comparison confirms in a twofold manner 

 the genuineness of the Pleskowitz specimen : first, by the fact 

 of their apparent external similarity, and secondly, by the great 

 differences the two stones exhibit in their internal structure. I 

 am greatly indebted to M. Kesselmeyer for the courtesy with 

 which he has communicated to me everything he has as yet 

 ascertained in his laborious researches among old writings about 

 these aerolites. That gentleman informs me of a passage in 

 Dr. John Mayer's work, Beytrag zur Geschichte der meteorischen 

 Steine in Bbhmen, Dresden, 1805, wherein Mayer quotes from a 

 most scarce treatise (not in the British Museum) by Stepling, 

 de Pluvid lapided anni 1753, ad Strkow et ejus causis Meditatio, 

 Pragse, 1754, in which he describes no less than three stonefalls 

 in Bohemia, viz. : — 



