38 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL, I48 



fit into fallout patterns or were witnessed falls. Such a percentage 

 can hardly be a coincidence. 



The fact that hexahedrites are chemically simple and apparently 

 without silicate inclusions raises the possibility that hexahedrites may 

 represent fragments from the core of a larger body. Most theorists 

 agree that the core should be essentially free from silicates, and from 

 a standpoint of quantity, core material should be less abundant than 

 material from the surrounding shells. The hexahedrites meet these 

 two rather basic requirements of core material. 



Many of these topics have been presented before societies and 

 symposia since 1950. Critical comments generally can be divided 

 into two types : ( 1 ) Meteoritic statistics are too limited to support 

 these groupings; (2) Conditions necessary to accompHsh these 

 selected fallout groupings of hexahedrites are difficult to reconcile 

 with basic concepts of astrophysics. 



Perhaps some of these criticisms are still valid, but new finds of 

 hexahedrites, as well as investigations of other scientists, have pro- 

 duced more facts to support these proposals than to disprove them. 

 Thus, more investigators seem to agree with the theme here proposed 

 than to disagree with it. 



Many assume that meteorites are equally distributed over the earth 

 but because they are discovered by accident, their recovery is limited 

 to fairly settled regions of the surface of the earth. However, these 

 70 hexahedrites are not uniformly scattered over the area from which 

 meteorites have been recovered. About 70 percent of them are con- 

 centrated into 6 geographic areas, and the points of fall or discovery 

 within these areas suggest that they fell as a shower. 



The long axes of these strewn fields exceed those of the observed 

 falls of any meteorite, yet are about equal to the paths of several 

 observed fireballs and some of the witnessed displays of falling 

 meteorites. The long axes of the scatter of the individuals in the 

 different geographic areas lie in essentially a northeast-southwest 

 direction. 



LITERATURE CITED 



Axon, H. J. 



1962. Dendritic structure in the Nedagolla ataxite. Nature, No. 4854, 

 pp. 567-568. 

 Brown, H. See Goldberg et al., 1951. 

 Cohen, E. W. 



1903. Meteoritenkunde, Heft 3, p. 168. 

 Daubree, G. a. 



1875. Compt. Rend., Acad. Sci. Paris, vol. 81, p. 597. 



