Pages 



TLATE I. 



Fig. 1. Pallasite. Atacama, Bolivia. 



A tracing made from the polished surface of a specimen. The coloring is conventional in this 

 and in the next three figures. The yellow portions are the olivine grains, while the gray- 

 reticulated portion indicates the metallic iron and pyrrhotite, — since no distinction of the 

 different constituents was possible in a tracing except to divide them into silicates and 

 metallic portions 70 



Fig. 2. Pallasite. Krasnojarsk, Siberia. 

 Tracing, as in Fig. 1 71, 72 



Figs. 3, 4. Pallasite. Rittersgrun, Saxony. 



Tracings of two opposite sides of the same polished slab. All these tracings are of natural size 



and form, so far as it was possible to make them 72, 73 



Fig. 5. Pallasite, — Cumberlandite. Iron Mine Hill, Cumberland, Rhode Island. 



A slightly magnified portion of a section. The dark portions represent magnetite, and the light 

 parts the olivine with a minute portion of feldspar. While in the four preceding figures the 

 sponge-like structure of the metallic parts with the enclosed silicates could alone be shown, 

 in this and in the following figures the minerals are in general differentiated, and the fidelity 

 of the lithographer's work, in representing the form, structure, Assuring, coloring, etc. of the 

 natural section, will be appreciated by all familiar with such rocks. This figure shows the 

 same sponge-like structure as the preceding figures, but with the metallic iron replaced by 

 its oxidized form 75, 76 



Fig. 6. Pallasite, — Cumberlandite. Iron Mine Hill, Cumberland, Rhode Island. 



This figure is from a section of the same rock-mass as the preceding, and shows the same general 

 structure ; but the olivine of Fig. 5 is here replaced by serpentine, which retains the outlines 

 of the former, and marks its fissures by secondary magnetite grains 78, 79 



