PORTION OF THE COSMOS. AEROLITES. 443 



of iron and nickel : so that the presence of the nickel, which 

 is a constant ingredient (on an average 10 per cent., some- 

 times rather more, and sometimes rather less), is justly re- 

 garded as an excellent criterion of the meteoric character of 

 the entire mass. It is simply an alloy of two isomorphous 

 metals, not a combination in definite proportions. We also 

 mid intermixed in smaller quantities cobalt, manganese, 

 magnesium, tin, copper, and carbon. The last-named sub- 

 stance is partly mechanically interspersed in the form of 

 graphite difficult of combustion, and partly chemically com- 

 bined or united with iron ; analogous, therefore, to much 

 bar-iron. A mass of meteoric iron also always contains a 

 peculiar combination of phosphorus with iron and nickel, 

 which substances, on dissolving the iron in hydrochloric 

 acid, remain behind in the form of microscopic crystalline 

 needles and lamellae of a silvery whiteness." 



" B. Meteoric stones, more strictly so called, are usually 

 divided, according to their external appearance, into two 

 classes. In one of these, the apparently homogeneous and 

 principal portion of the mass shews interspersed grains and 

 spangles of meteoric iron, which are attracted by a magnet, 

 and are quite similar in their nature to meteoric iron, found 

 by itself in larger masses. To this class belong, for example, 

 the stones of Blansko, Lissa, Aigle, Ensisheim, Chantonnay, 

 Klein Wenden near Nordhausen, Erxleben, Chateau-Eenard, 

 and Utrecht. The other class is free from metallic inter- 

 mixtures, and presents rather a crystalline assemblage or 

 mixture of different mineral substances ; as, for example, in 

 the stones of Juvenas, Lontalax, and Stannern." 



After the first chemical examinations of meteoric stories 

 made by Howard, Klaproth, and Yauquelin, the possibility 



