LettersDiscussion and Correspondence THE GRAND GULF FORMATION By E. W. Hilgard See allHide authors and affiliations Science 07 Aug 1903:Vol. 18, Issue 449, pp. 180-182DOI: 10.1126/science.18.449.180-a E. W. Hilgard 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.