£00 EEPORT 1869. 



reduction and oxidation of various minerals (see Eeport for 1868, p. 415), 

 led M. Daubree to the conclusion that the latter process of imperfect scori- 

 fication, like that which the materials of the earth's crust appear to have 

 comphtely undergone by oxidation, represents the original process of forma- 

 tion of meteorites. In the rare aluminiferous meteorites of Juvenas, Jonzac, 

 Stannern, and Petersburgh (U. S.), the crystallization, like that of granite on 

 the earth, can only have taken place in the presence of water ; since their 

 felspathic ingredients are converted into glass or vitreous slags by fusion. 

 Some new points of interest on the classification of meteorites *, and on the 

 recent acqiiisitions in the Paris Museum of Geology of aerolitic specimens, are 

 added by M. Daubree to the former chapters of his original researches, 

 which are otherwise reproduced in the present pamphlet without change. 

 Among the recent specimens acquired at Paris, not less than 950 perfect 

 aerohtes of the stonefall of Pultusk (1868, January 30th), varying from 

 the size of a hazel-nut to that of a hen's eg^, have lately been deposited by 

 M. Daubree in the Geological Museum. 



6. In ' Cosmos ' for January 18th, 1868, M. Stanislas Meunier communi- 

 cates a new chemical test for distinguishing the protosulphuret of iron (Fe S) 

 from the ordinary terrestrial magnetic sulphuret or pyrrhotine (Fe, SJ. The 

 former, even when slightly supersulphurctted, precipitates metallic copper from 

 its solutions ; but when the proportion of sulphur approaches to that contained 

 in pyrrhotine, and in the case of the mineral pyrrhotine itself, no such pre- 

 cipitate is produced. The fact that the magnetic sulphuret of iron (troilite) 

 found in meteorites remains inactive, or " passive," when placed in a solution 

 of sulphate of copper, leads M. Meunier to conclude that its chemical 

 formula and mineralogical characters approach more nearly to those of 

 pyrrhotine (Fe. SJ than to those {ydih. which it is usually compared) of the 

 protosulphuret of iron, Fe S. A paper by the same author, in the ' C'osmos ' 

 for March 21st, 1868, describes at length the process employed in the labora- 

 tory of the Paris Museum of Geology for analyzing meteoric irons. 



7. "Licht, Warme, und Schall bei Meteoritenfallen," von "W. v. Hai- 

 dinger (extracted from the Yienna Academy Sitzungsbericht, vol. Iviii. 

 part 2, for October 8th, 1868). — An English version of the paper appears 

 in the Philosophical Magazine for April, 1869. 



Some remarks by M. Daubree and M. Meunier in the foregoing papers 

 appearing to admit of theoretical exceptions, the opportunity of reviewing the 

 facts recently observed regarding the falls of the meteorites in different parts 

 of the globe, and the conclusions to which they lead in confirmation of M. 

 Haidinger's views of their interpretation, is made the occasion of a clear 

 exposition by the eminent mineralogist of Vienna of the progress of aerolitic 

 science during the long time in which it has engaged his attention, and 

 especially of the rapid strides which, owing to the able geological and astro- 

 nomical inquiries which have .recently been devoted to the subject, it has 

 principally been enabled to make during the last few years. 



8. " Recherches sur la composition et la structure des Meteorites," par M. 

 Stanislas Meunier (in 4to, pp. 73 : , Gauthier A^illars, Paris, 1869. — A thesis 

 presented to the Faculty of Sciences of Paris for the award to the author of 

 the degree of Doctor in Physical Science). — The results of special methods of 

 analysis employed in foreign, and original researches on the composition 

 of a large number of meteoric irons are recapitulated by M. Meunier at 

 the end of the memoir, in the following general conclusions : — ■ 



* ' Comptes Renclu3 ' for March 25 and April 2, 18G7, ancT subsequent Numbers, 



