Laserfiche WebLink
<br />PREFACE <br /> <br />The series of manuals on techniques describes procedures for planning <br />and executing specialized work in water-resources investigations. The ma- <br />terial is grouped under major subject headings called books and further <br />subdivided into sections and chapters; section B of book 4 is on surface <br />water, <br />The unit of publication, the chapter, is limited to a narrow field of <br />subject matter, This format permits flexibility in revision and publication <br />as the need arises, <br />Provisional drafts of chapters are distributed to field offices of the D.S, <br />Geological Survey for their use. These drafts are subject to revision because <br />of experience in use or because of advancement in knowledge, techniques, <br />or equipment, After the technique described in a chapter is sufficiently <br />developed, the chapter is published and is for sale by the Superintendent <br />of Documents, D.S, Government Printing Office, Washington, D.C. 20402. <br /> <br />III <br />