2 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 73 



binding or cementing constituent holding the fragments together. 

 The manner in which the metal projects into the interstices of the 

 silicates is to be noted. Instances of this nature are common in many 

 chondritic meteorites, both crystalline and otherwise. 



Figure 2 of the same plate is that of a fragment of a dark chon- 

 dritic stone embedded with others of a quite different nature, as 

 described in my paper entitled " The Cumberland Falls, Kentucky, 

 Meteorite," published in 1920.* 



Attention was there particularly called to the fine threadlike forms 

 sometimes assumed by the metal, (1) white in the figure. These 

 veinlets or stringers vary from 1 or 2 millimeters in thickness to mere 

 films of only microscopic dimensions, and divide and subdivide 

 repeatedly, their ramifications reaching out and completely surround- 

 ing or penetrating into the silicates along cleavage or fracture lines. 



A noticeable layer of metal, too, lies along the boundary line of 

 the fragment, a condition which it was thought might indicate a 

 deposition of the material since the consolidation of the stone in its 

 present brecciated form. 



Figure 3 is that of a slice of a pallasite belonging to the Kokicky 

 group, found at Admire, Kans., and described in 1902.^ 



The dark areas are olivine, the white (1), nickel-iron with scattered 

 particles of schreibersite (2), and troilite (3). The feature of im- 

 portance in the present instance, is the angular character of the 

 olivines. It is to be noted that they are not products of crystalliza- 

 tion, in situ. They are rather fragments, in some cases mere splin- 

 ters, as sharply angular as so much shattered glass. These are firmly 

 embedded in the metal with no signs of corrosion or alteration in- 

 dicative of heat or moisture. The same is true of the Eagle station 

 meteorite and others of its class. 



Figure 4 is from the Four Corners meteorite. This consists largely 

 of a coarsely granular aggregate of metal inclosing fragments of 

 disintegration from a fine granular pyroxenic rock, now in some 

 cases reduced to mere sand. The metal, as shown at (1) completely 

 incloses these silicate particles (2) and in places penetrates slightly 

 into their interiors. The stony fragments are all unchanged, with 

 no sign of corrosion by heat or otherwise, even when in the condi- 

 tion of finest sand, no slag nor glass ; the contact is as sharp and free 

 from signs of alteration as though the admixture had taken place 

 when cold. 



The above illustrations are sujflicient, it is thought, to show that, 

 so far as chondritic meteorites and those of the Rokicky and Four 

 Corners type are concerned, the metal is the last constituent to con- 

 geal, and that it is probably wholly of secondary origin. The ques- 



* Proc. U. S. Nat. Mus., vol. 57, 1920, pp. 97-105. 

 BIdein, vol. 24, 1902, pp. 907-913. 



