THE ORIGIN AND STRUCTURE OF METEORITES. 383 



him to endeavor to ascertain their origin during his voyage to North- 

 ern Greenland in 1870. After much searching, with the aid of what 

 directions the natives could give him, he at last found the object of 

 his investigations in the hill of Blaaf jeld, or Ovifak, near Disco Isl- 

 and. Blocks of iron were lying on the shore at the foot of a high 

 cliff composed of basalt and conglomerates of the same rock in alter- 

 nation ; and more than twenty masses, containing not less than twenty- 

 one thousand kilogrammes of metallic iron, were collected within a 

 small space. They were at first supposed to be of meteoric origin, be- 

 cause they contained nickel, and exhibited figures which had been 

 regarded as peculiar to meteoric iron. But this view was proved to 

 be incorrect when M. Steenstrup, under a commission from the Danish 

 Government to investigate the conditions under which the iron oc- 

 curred, found, at one point on the coast, native iron actually imbedded 

 in the basaltic rocks, the appearance of the larger grains of which was 

 precisely similar to that of the scattered blocks previously found. The 

 presence, in the eruptive rocks of the earth, of iron alloyed with nickel, 

 similar to meteoric iron, and having the crystalline texture which had 

 previously appeared to be an exclusive characteristic of the latter, has 

 therefore become incontestable. It is proper to add that the metal in 

 this condition is not a fortuitous and isolated accident in Greenland, 

 but that it is found in many places and over considerable districts. 



The geological structure of the northern part of that country is 

 especially distinguished by the development of eruptive rocks of a 

 relatively very recent age. It is one of the largest masses of basalt 

 with which we are acquainted. It begins at the sixty-ninth degree of 

 latitude, and disappears near the seventy-sixth degree, under the vast 

 continental glacier which prevents all further exploration of the sur- 

 face. It is reasonable to suppose that the eruptions of which these 

 rocks are the result brought up metallic iron, of which they seem to 

 indicate the existence of large masses in the deep interior. This 

 fact has also to be taken account of in the theory of terrestrial mag- 

 netism. 



After having sketched, twenty years ago, the numerous features of 

 resemblance between the meteorites and the deep terrestrial rocks, and 

 having shown how some of them can be imitated by a partial deoxi- 

 dation of those rocks, I added : " There is nothing to prove that be- 

 neath those aluminiferous masses which have furnished, in Iceland, for 

 example, lavas analogous to the meteorites of Juvinas, that beneath 

 our peridotic rocks which the meteorite of Chassigny closely resem- 

 bles, there may not be found masses in which native iron begins to 

 appear, or resembling meteorites of the common type ; then, below 

 these, types richer and richer in iron, of which the meteorites offer a 

 series of increasing density, from those in which iron represents nearly 

 half the weight of the rock to massive iron." Five years after these 

 lines were written, the great masses of native iron alloyed with nickel, 



