METEORITES OF NORTH AMERICA. 77 



BOCAS. 



Hacienda de Bocas, San Luis Potosi, Mexico. 



Latitude 22° 12' N., longitude 100° 58' W. 



Stone. White chondrite (Cw) of Brezina; Luceite (type 37, sub-type 2) of Meunier. 



Fell November 24, 1804. 



Weight (assignable) 14 grams. 



Nothing is known of the size, weight, or form of this meteorite. 



Castillo stated to Burkart ' that the fragments in his possession showed a whitish-gray 

 crystalline structure penetrated by black filaments mixed with grains of nickel-iron. 



In his catalogue Castillo 3 states that the meteorite fell November 24, 1704 (sic), in the 

 hacienda of Bocas, and that it is preserved in small fragments in the collection of the School of 

 Engineers in Mexico, formerly the College of Mining. Brezina 2 classifies it as a white chondrite. 



The few grams known are distributed. 



BIBLIOGRAPHY. 



1. 1865: Burkart. Verhandl. naturhist. Verein Bonn, Bd. 22 (Sitzber.), p. 71. 



2. 1885: Brezina. Wiener Sammlung, pp. 177 and 232. 



3. 1889: Castillo. Meteorites, p. 13. 



Bolson de Mapimi. See Coahuila. 



BOTETOURT COUNTY. 



Botetourt County, Virginia. 



Latitude 38° N., longitude 79° W. 



Iron. Ataxite (D) of Brezina. 



Found 1850; described, 1866. 



Weight, "A large mass, not easily transported on horseback." 



This iron was described by Shepard 1 as follows: 



This iron was discovered about 1850 in a mass so ponderous that the finder, having attempted to transport it on 

 horseback a number of miles to his house, was obliged to abandon the undertaking. He left it upon a stone wall by 

 the road side, after having (with the assistance of a negro who happened along with a hammer) detached two or three 

 small angular fragments. These were afterward given to Mr. N. S. Manross, who took them with him to Gottingen, 

 where, in the laboratory of Professor Wohler, he analyzed one of them so far as to determine the presence of nickel in 

 the unusually high proportion of 20 per cent. 



It is whiter than most irons, extremely close and homogenous, with exception of a few minute pyritic grains. 

 Specific gravity, 7.64. Fracture fine granular, like cast steel. It does not give the Widmannstatten figures. 



Brezina 3 in 1885 referred Botetourt to the compact irons, but added: "possibly belonging 

 to the Cape iron group." 



Wulfing 4 drew attention to the fact that possibly the specimen entered in the Gottingen 

 catalogue "1886: Virginia, North America (from a petroleum well)," and representing 1.5 gr., 

 belongs here. The presumption based on the identity of the locality, "Virginia," is the more 

 probable inasmuch as the date also corresponds with that of the publication of Shepard's 

 notice and that fragments may. have come to Wohler through Manross. 



An investigation of the Gottingen specimen by Cohen, 5 however, showed it both chemically 

 and physically to be an artificial iron. From a fragment in the Vienna Museum, labelled 

 Botetourt, 17 milligrams were analyzed by Sjostrom with the following result (II computed 



to 100): 



I II 



Fe 85.88 82.49 



Ni and Co 18. 23 17. 51 



104. 11 100. 00 



The specific gravity of 0.4511 grams, at 15.7° C (Leick), was found to be 8.1860. Since 

 this was the highest specific gravity hitherto known in meteorites, and as Shepard gave only 

 7.64, two determinations were made, each time in water and alcohol; these gave 8.1851 and 

 8.1870. The specimen showed no polar magnetism, and a specific magnetism of 0.44. 



