Geological Society of London. 571 



Discussion. — Mr. David Forbes having recently returned from Stockholm, where 

 he had the opportunity of examining these remarkable masses of native iron, stated 

 that they had been first discovered last year by the Swedish Ai-ctic expedition, which 

 brought back several blocks of considerable size found on the coast of Greenland, 

 The expedition of this year, however, has just succeeded in bringing back more than 

 twenty additional specimens, amongst which two were of enormous size. The largest, 

 weighing more than 49,000 Swedish pounds, or about 21 tons English, with a 

 maximum sectional area of about 42 square feet, is now placed in the hall of the 

 Eoyal Academy at Stockholm ; whilst, as a compliment to Denmark, on whose terri- 

 tory they were found, the second largest, weighing 20,000 lbs., or about 9 tons, has 

 been presented to the Museum of Copenhagen. 



Several of these specimens have been submitted to chemical analysis, which proved 

 them to contain nearly five per cent, of nickel, with from one to two per cent, 

 of carbon, and to he quite identical, in chemical composition, with many aerolites 

 of known meteoric origin. When polished and etched by acids, the surface of these 

 masses of metallic iron shows the peculiar figures or markings usually considered 

 characteristic of native iron of meteoric origin. 



The masses themselves were discovered lying loose on the shore, but immediately 

 resting upon basaltic rocks (probably of Miocene age), in which they appeared to 

 have originally been imbedded ; and "not only have fragments of similar iron been 

 met with in the basalt, but the basalt itself, upon being examined, is found to contain 

 minute particles of metallic iron, identical in chemical composition with that of the 

 large masses themselves, whilst some of the masses of native iron are observed to 

 inclose fragments of basalt. 



As the chemical composition and mineralogical character of these masses of native 

 iron are quite diflTerent from those of any iron of terrestrial origin, and altogether 

 identical with those of undoubted meteoric iron, Professor Nordenskiold regards 

 them as aerolites, and accounts for their occurrence in the basalt by supposing that 

 they proceeded from a shower of meteorites which had fallen down and buried them- 

 selves in the molten basalt during an eruption in the Miocene period. 



Notwithstanding that these masses of metallic iron were found lying on the shore 

 between the ebb and flow of tide, it has been found, upon their removal to Stockholm, 

 that they perish with extraordinary rapidity, breaking up and falling to a fine 

 powder. Attempts to preserve them by covering them with a coating of varnish have 

 as yet proved unsuccessful, and it is actually proposed to preserve them from destruc- 

 tion by keeping them in a tank of alcohol. 



Mr. Maskelyne stated that the British Museum already possessed a specimen of this 

 native iron, and accounted for its rapid destruction on exposure by the absorption 

 of chlorine from terrestrial sources, which brought about the formation of ferrous 

 chloride. This was particularly marked in the case of the great Melbourne meteorite 

 in the British M useum ; he had succeeded in protecting this, as well as the Greenland 

 specimen, by coating them externally, after previously heating them gently, with a 

 varnish made of shellac dissolved in nearly absolute alcohol. 



He considered it probable that a meteoric mass falling with immense velocity 

 might so shatter itself as to cause some of its fragments to inclose fragments of basalt, 

 and even to impregnate the neighbouring mass of basalt with minute particles of the 

 metallic iron ; but he considered the question of meteoric origin could only be decided 

 by examining the same mass of basalt at some greater distance from the stones them- 

 selves, so as to prove whether the presence of such metallic iron was actually charac- 

 teristic of the entire mass of the rock. 



Prof. Eamsay referred to the general nature of meteorites and to their mineral 

 relationship to the planetary bodies, and remarked that, supposing the earth to have 

 in part an elementary metallic core, eruptive igneous matter might occasionally bring 

 native iron to the surface. 



Mr. Daintree mentioned that he had been present at the exhumation of the 

 Melbourne meteorite, and that at that time there was little or no trace of any exuda- 

 tion of ferrous chloride, the external crust on the meteorite being not above 1/32-inch 

 in thickness. 



2. " On the Geology of the Diamond-fields of South Africa." By 

 Dr. John Shaw, of Colesberg. Communicated by Dr. Hooker, F.E.S., 

 F.G.S. 



