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terrestrial from one of meteoric origin has been lately ren« 

 dered more evident by the controversy as to the origin of 

 rfche large masses of iron, containing one or two per cent, of 

 nickel, and weighing 9,000, 20,000, and 50,000 lbs. respec- 

 tively, found in 1870 by Professor Nordenskiold on the 

 beach at Ovifak, Disko Island, Western Greenland (103 L). 

 A careful examination of the rocks of the neighbourhood 

 shows that the basalt contains nickeliferous iron disseminated 

 through it, and that the large masses, at first thought to be 

 meteorites, are very probably of terrestrial origin, and have 

 been left exposed upon the sea-shore through the weathering 

 of the rock which originally enclosed them. Malleable 

 metallic nodules extracted from the rock itself were found 

 to contain as much as 6*5 per cent, of nickel. Some assert 

 that the basalt and the nickel-iron have been expelled together 

 from great depths below the earth's surface, while others 

 consider that the nickel-iron is due to the reduction of the 

 basalt in its passage through the beds of lignite and other 

 vegetable matter found in the vicinity. 



The minerals forming the stony part of the siderolites and 

 aerolites are almost entirely crystalline, and in most cases 

 present a peculiar 'chondritic' or granular structure, the 

 loosely coherent grains being composed of minerals similar 

 to those which enclose them, and containing at times minute 

 particles of iron disseminated through them. The minerals 

 mentioned above as occurring in meteorites are such as are 

 very characteristic of the more basic terrestrial rocks which 

 have been brought from considerable depths below the earth's 

 surface. Several attempts to classify aerolites according to 

 their mineralogical constitution have been made, but it can- 

 not be said that any of them is very satisfactory : seeing 

 that even in the same stone there may be much difference in 

 its parts a perfect classification on such a basis is scarcely to 

 be hoped for. About nine out of every ten of the stony 

 meteorites belong to a group to which Rose has given the 

 name of Chondrites: their crust is black and always dull: the 

 fracture is grey and is rough to the touch : they present a very 

 fine-grained but crystalline matrix or paste consisting of 

 nickel-iron, troilite, chromite, a soluble silicate (olivine) and 



