Read by Prof. L. F. Brady at the Fourth Annual Meeting of the Society for Research on Meteorites, University of California at Los Angeles, June 23 and 24, 1936. Reprinted from Popular Astronomy, Northfield, Minnesota, 1936, vol: 44, pp. 381–383. References to Mineralogical Abstracts [M.A.] and the Mineralogical Magazine have been inserted in this reprint.