LettersDiscussion and Correspondence POSITIVE RAY ANALYSIS OF LITHIUM By A. J. Dempster See allHide authors and affiliations Science 15 Apr 1921:Vol. 53, Issue 1372, pp. 363-364DOI: 10.1126/science.53.1372.363-a A. J. Dempster Find 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 above.