EICHWALD — ALEUTIAN GEOLOGY. 7 



in iron, which, under certain circumstances, may reach the surface 

 (although, as he says, Greenland would seem to be a peculiarly 

 favourable region for the occurrence of such a phenomenon), the 

 author indicates that the basaltic rocks themselves, which contain 

 more than 20 per cent, of oxide of iron, may, on reaching the sur- 

 face, have undergone a partial reduction ; and in support of this view 

 he points out that between 69° and 72° N. lat. Greenland contains 

 numerous thick layers of lignite, especially in Disco Island, where 

 Ovifak is situated. 



The author calls attention, however, to the fact that the singular 

 mixture of substances which are decomposed or set free at a very 

 moderate heat, seems to be incompatible vsdth the temperature 

 through which these bodies, from other circumstances, may be 

 assumed to have passed, and indicates that this mode of association 

 is presented also by the carbonaceous meteorites belonging to four 

 falls which have taken place since the beginning of this century*. 

 In other meteorites free oxide of iron has very rarely been indicated ; 

 those which are rich in carbon contain their iron almost entirely 

 in the state of oxide. The author refers to a reaction investigated 

 by Stammer and Griiner in which oxide of carbon in presence of 

 an oxide of iron becomes split, producing a deposit of carbon partly 

 combined with iron and partly mixed with the oxide of that metal, 

 which seems to him to present some analogy with the constitution of 

 the carbonaceous meteorites. 



The presence in these masses of so large a proportion of soluble 

 salts was at first regarded by the author as distinguishing them from 

 meteorites ; but in his second paper he shows that in several cases 

 chlorides and other soluble salts have been detected in meteorites by 

 C. T. Jackson, Lawrence Smith, Shepard, and others, and remarks 

 especially upon the absence of chloride of sodium from the masses 

 found at Ovifak. He notices further that, from the mode in which 

 the polished surfaces become moistened and oxidized during ex- 

 posure, it is evident that the deliquescent salts are not uniformly 

 distributed throughout the masses, and that the preservation of the 

 masses on the coast of Greenland is due to the feeble tension of the 

 vapour of water in the polar regions, and would by no means be 

 manifested under other cHmatic conditions. Whilst recognizing the 

 probable meteoritic origin of these masses, the author thinks that 

 they seem to elucidate the nature of the deeper-seated parts of our 

 globe. [W. S. D.] 



2. Geology 'of the Aleutian Islands. By E. von Eichwald. 



[Proc. Imp. Geol. Inst. Vienna, May 7, 1872.] 



These islands, which are remarkable for their glaciers and serial 



volcanoes, form, with the peninsula of Aliaska, a geological whole, 



and seem, according to the author, to be in process of elevation, so 



* These are the falls of Alais (15th March, 1806), of Cold Bokkeweld, Cape of 

 Good Hope (13th October, 1838), of Kaba, in Hungary (15th April, 1857), and of 

 Orgueil (14th May, 1864). 



