64 STUDIES FOR STUDENTS 



there can be little doubt that the mass was made up by the 

 aggregation of solid angular fragments. The meteorites of 

 Zacatecas and Kendall counties have a similar structure, though 

 the component fragments are much smaller. 



Some of the iron-stone meteorites have likewise a brecciated 

 structure resulting from the imbedding of angular masses of sili- 

 cates in a metallic base. The meteorite of Copiapo, for example, 



Fig. 6. — Brecciated structure. Mt. Joy Meteorite. 



has such a structure and its formation is exactly analogous, in the 

 view of Meunier, to the dike breccias produced on the earth by 

 intrusive igneous eruptions tearing off fragments of the rock 

 through which they have ascended and enclosing them in its 

 pasty mass. In this case the intrusive matter was fused nickel- 

 iron. In other iron-stone meteorites, such as Vaca Muerta and 

 Eagle Station, the silicate fragments are likewise angular. 

 Reichenbach is authority for the statement that the iron in these 

 adapts itself to the form of the stone rather than the contrary. 



The fragments forming the breccia in stone meteorites are 

 often of considerable size. The largest which I have noted in 

 the stony meteorites (Weston) is about one cubic inch in 

 contents. 



