Standard methods, by American Public Health Association                  61462   [Full title: Standard methods for the examination of water and sewage]   [Link: http://www.gutenberg.org/6/1/4/6/61462 ]   [Files: 61462-0.txt; 61462-h.htm] Thanks to Richard Tonsing and the Online Distributed Proofreading Team at http://www.pgdp.net (This file was produced from images generously made available by The Internet Archive) Chuck