46 MERRILL AND STOKES 



as having some bearing on the origin of the iron meteorites, 

 the writer regarding them as residual masses of larger, coarse, 

 granular forms from which the silicates have been lost through 

 disintegration, perhaps before reaching the earth. Chromite in 

 black specks is often associated with the sulphides, but does not 

 in the section present good crystal outlines. 



The presence of alumina and alkalies, as indicated by Dr. 

 Stokes's analyses, caused a careful search to be made for the 

 presence of feldspar, but none was found, ^ though it is possible 

 that sundry minute, clear and colorless, doubly refracting par- 

 ticles may be thus referred. These never show twin structure, 

 cleavage lines, nor other physical properties such as permit a 

 definite determination. It is more probable, however, that 

 these elements are accessory constituents of the enstatite. If 

 such is the case, the stone, as shown by the analyses and micro- 

 scopic investigation, is composed of nearly equal parts of highly 

 ferriferous olivine and enstatite, the latter being low in mag- 

 nesia in proportion as it is high in the accessory elements. 



Much of the interstitial material of the groundmass is so fine 

 and dust-like that it is impossible to determine its mineral 

 character in the thin section. After repeated trials the de- 

 vice was adopted of taking some of the fragments, several 

 grammes in weight, and after dusting them carefully with a 

 camel's hair brush and blowing upon them to remove all 

 external dust particles, placing them in a funnel upon a 

 piece of silk bolting cloth and allowing a half liter or so of 

 distilled water to trickle over them, drop by drop; the liquid 

 was then evaporated in a porcelain dish and the resultant 

 dust, which is believed to correctly represent the true ground- 

 mass in an unaltered condition, was collected and submitted 

 to a microscopic examination. It was found to be composed of 

 beautifully fresh, sharply angular splinters, mainly of enstatite, 

 though with some olivine and black glass (PI. Ill, fig. i). 



Cross sections of the thin portions of the crust (the highest 



1 H. L. Ward (Am. Jour. Sci., Dec, 1899, p. 414) states that the stoue is 

 feldspathic, and classes it with Meunier's montrejites. I cannot agree with 

 him in this. It is essentially non feldspathic and belongs more nearly to Bre- 

 zina's group 29, Kugelchen chondrite (C"). — G. P. M. 



