ArticlesAddress PROBLEMS OF PHYSICS By O. W. Richardson See allHide authors and affiliations Science 30 Sep 1921:Vol. 54, Issue 1396, pp. 283-291DOI: 10.1126/science.54.1396.283 O. W. Richardson 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.