﻿Huntington — Crystalline Structure of Iron Meteorites. 289 



rior portions solidified, these also crystallized more or less per- 

 fectly, but forming smaller and. smaller plates. 



Figure 2 shows, double the natural size, one face of a very 

 perfect octahedron broken out from the Putnam County mete- 

 orite. This iron appears by oxida- 

 tion of the surface to break up 

 into octahedrons and acute rhombic 

 prisms. The octahedron represented 

 in fio". 2 was so loose in its structure 



o 



that it was necessary first to mount 

 it in pitch before grinding the face 

 in order to prevent the plates from 

 splitting off. Here the character is &_L 

 much the same as in the previous 

 one, except that the plates are smaller, 

 and at the points a, b and c the iron 

 is perfectly granular, showing no 

 signs of crystallization. Moreover, 

 the groundmass, instead of contain- 

 ing the combs above mentioned, has been broken up by a 

 series of irregular cracks into coarse grains, very much like a 

 mass of crackled glass. Another meteorite which most beau- 

 tifully illustrates the octahedral arrangement is the Tazewell 

 (Claiborne Co.) iron, fig. 3. Here the figures brought out by 

 etching are very sharply defined, but are so small that, in some 

 parts of the field, it seems as if there were almost no limit to 

 the fine bands as seen with an ordinary pocket lens. The 

 bands, though small, exhibit all the features of the coarser 

 Widmanstattian figures. On the exterior of the mass, small 

 octahedral planes are distinctly visible, and a crack, shown 



Putnam Co., Georgia. 



Tazewell, Claiborne County.* 



* The illustrations of this paper were 1 made by the Lewis Engraving Company, 

 and although in the details they are faithful reproductions of the drawings from 

 which they were taken, yet the lines are all too heavy, and give the idea of a 

 much coarser structure than the meteorites actually present. This is especially 

 true of the above cut. 



