ArticlesShorter Articles RADIO-ACTIVE MINERALS See allHide authors and affiliations Science 15 Feb 1901:Vol. 13, Issue 320, pp. 274DOI: 10.1126/science.13.320.274-b GEO. B. PEGRAMFind this author on Google Scholar Find this author on PubMed Search for this author on this site Article Info & Metrics eLetters PDF This is a PDF-only article. The first page of the PDF of this article appears below.