78 Notices of Memoirs — Bauhrde^ Classification of Meteorites, 



sideres, and Cryptosideres, according as tlie iron is — in great quan- 

 tity (Sierra del Chaco) ; in small quantity (Saint-Mesmin, Aumale, 

 etc.); or in indiscernible proportion (Juvinas, Chassigny). These 

 sub-divisions are far from having the same value; but they each 

 correspond to sensible variations in the density. 



The fourth sub-division of coherent meteorites is that of Asideres, 

 corresponding to the Asiderites, which is characterized by the ab- 

 sence of metallic iron. The number of specimens of this latter 

 group is very limited, and nearly restricted to the carbonaceous 

 meteorites (Alais, Orgueil). Such is the principle on which the 

 classification is based : the differences and relations which are found 

 in the two types of meteorites are shown in the preceding table. 



Note. — The meteorite of Sierra del Chaco noticed above resembles, 

 according to M. Gustav Eose, that of Hainholz, described by 

 Keichenbach. Both are very different from other meteorites ; they 

 present the remarkable peculiarity of containing Augite, which is 

 not accompanied by anorthite, as in the meteorite of Juvenas, but 

 which is, on the contrary, associated with iron containing nickel, 

 with peridot, and magnetic pyrites. Besides, the nickel, iron, and 

 pyrites, on the one hand, and the peridot and augite on the other, 

 occur in nearly equal proportions. For these meteorites M. Rose 

 has proposed a special name, that of mesosiderites} The arrange- 

 ment of the meteorites in the museum of the Berlin University, by 

 M. G. Rose, is based on their mineral character, and forms two 

 divisions — the metallic and the stony meteorites, the first containing 

 meteoric iron and the Pallasite, the second the Chondrites, Howardites, 

 Chassignites, Chladnites, and lastly the Eukrites, which contain 

 augite as well as anorthite. The meteorites of Alais and the Cape 

 (and we may add that from Australia) contain carbon, and form 

 with the mesosiderites two other groups. 



We may here refer to the collection of meteorites in the British 

 Museum, which, under the able direction of the present keeper, has 

 been so greatly augmented that it now stands unrivalled both for 

 extent and value of the specimens, the number being about 260. 

 They are arranged in two cases ; one contains the stony varieties or 

 Aerolites, characterized by the presence of minute stony spherules. 

 These are the Chondrites, Howardites, Chassignites, etc. They all 

 contain meteoric iron in fine particles disseminated through them. 

 In the other case are displayed the Siderolites and the Aero-siderites. 

 The former are masses of meteoric iron, containing stony matter ; the 

 latter consist of the metallic alloy of iron and nickel, with small 

 amounts of other metals known as "meteoric iron." They also 

 contain mechanical admixtures of compounds of these metals with 

 phosphorus and with sulphur. — J. M. 



1 Vide Sorby on the microscopical structure of meteorites. Proc. Roy. Soc, June, 

 1864. 



