488 MEMOIRS NATIONAL ACADEMY OF SCIENCES, VOL. XIII. 



A separate examination of the troilite nodules proved them to consist of ferrous sulphide with a little nickel and 

 traces of manganese and chromium. The nickel may very possibly have existed in the form of minute granules of 

 nickel iron or schreibersite, and the chromium may in like manner be referred to an admixture of little particles of 

 daubreelite. 



The most interesting point about this specimen is perhaps the probability of its forming a separate portion of the 

 same meteoric fall from which was derived the large iron meteorite, weighing 1,635 pounds, first described by Colonel 

 Gibbs in 1814, and which has long been a prominent object in the mineralogical collection of Yale College at New 

 Haven, Connecticut. The latter is said to have been found "near the head of Trinity River, a few miles west of the 

 Cross Timbers, Texas, latitude 32° V N., longitude 95° 10' W. of London." It is said to have been "one of a large 

 number of meteoric masses which are reported to exist at the locality mentioned above." The statement of locality 

 is not quite clear; the spot designated by latitude and longitude is in the northern part of the present Cherokee County 

 near the line of Smith County and rather on the headwaters of the Neches than of the Trinity, though not far from 

 the latter and about 240 miles from the locality of Wichita County where the meteorite now described was found. 

 Even such a distance perhaps does not altogether exclude the idea of simultaneous fall, and it is of course quite possible 

 that the mass found to be regarded with attention and veneration by the Indians may have been carried to the spot 

 where they afterwards preserved it. There seems to be some uncertainty as to how many meteoric irons from Texas 

 have before now been noticed and are to be foimd in the mineralogical collections of the world. In a catalogue of the 

 collection of Prof. C. U. Shepard, published in 1857, in the second part of his treatise on mineralogy, page 436, there 

 is mentioned a meteoric iron from "Texas (Red River), U. S. A., found in 1808." In Rammelsberg's Ilandbuch der 

 Mineralchemie (Leipzig, 1860) are noticed, page 917, specimensfrom "Red River in Louisiana," and from "Texas," 

 with the statement that according to Partsch these are probably identical; this opinion is undoubtedly correct; the 

 analyses quoted show that both represent the Yale College specimen. In the recent (1880) catalogue of meteorites in 

 the collection of the Indian Museum at Calcutta No. 108 is quoted on page 3S as two specimens from " Red River, Texas, 

 U. S. A., found in 1814," No. 27, on page 31, as a specimen which "apparently has been fired, from Denton County, 

 Texas, U. S. A., found in 1856," and No. 39, on page 32, as from "Brazos River, Texas, U. S. A., found in 1856." It 

 may be questioned whether Nos. 27 and 39 refer to portions of the same or of different masses; the same date is given, 

 but the shortest distance from any part of Denton County to the Brazos is about 40 miles, this county being traversed 

 by affluents of the Trinity. The specific gravity of the iron now described agrees closely with that reported for the 

 Gibbs meteorite of the Yale College collection. The results of the chemical analysis are also very similar to those 

 obtained for the latter by B. Silliman, jr., and Hunt. It is stated that this latter "incloses a few small masses of 

 magnetic pyrites"; this statement probably referring to troilite nodules like those which are conspicuous in closures in 

 the University of Texas specimen. The Widmannstatten figures developed by etching this University of Texas iron 

 do not closely resemble those of the Yale College specimen, as shown in a lithographed figure published in connection 

 with the (Gottingen) inaugural dissertation on metallic meteorites of William S. Clark (1852), copied from one published 

 by Prof. B. Silliman, jr., but the difference in appearance may be largely due to difference in the planes of section 

 in relation to those of crystallization in the particular pieces submitted to the etching process. 



In the Vienna Catalogue for 1 885 Brezina 5 groups Wichita among octahedrites with coarse 

 lamellae, Arva group, and describes it as follows, giving two plates to illustrate its appearance: 

 Most striking are the great troilite inclusions which are surrounded with a shell of graphite, then one of schrei- 

 bersite, finally one of swathing kamacite. * * * Wichita shows very beautifully on account of the great length 

 of its bands, extraordinarily long fields, which are rilled partly with dark plessite, partly with combs. 



From the structure, Brezina further asserts the improbability of a union of Wichita with 

 Cross Timbers. 



Cohen and Weinschenk 8 give the following analyses of some shavings and a section of 

 this meteorite: 



For the shavings— 



Fe Ni Co 

 91.67 7.93 0.40 =100 

 For the section- 

 Nickel iron 85. 41 



Tsenite 1. 47 



Schreibersite 6. 07 



Crystals resembling cohenite 6. 04 



Angular fragments 1. 01 



100.00 



The crystals of cohenite gave : 



Fe Ni Co C 



82.42 9.96 2.20 5.08 =99.66 



The cohenite is described as brittle and metalloid. 



The tsenite gave : 



Fe Ni Co Cu P Schreibersite 



60.73 30.46 1.46 trace 0.16 5.73 =98.54 



