150 Trans. Acad. Sci. of St. Louis. 



(4) That in the form of dust is probably the chief 

 meteoritic augmentation to the earth's volume, with the 

 abundance of metallic grains in the desert soils and arctic 

 snows as evidence. 



(5) That the principal ultimate source of ore materials 

 is possibly meteoritic in character rather than magmatic. 



Issued December 2D, 1910. 



