An instrument for measuring pressure head in a conduit, tank, or soil-it is a small diameter water well used to measure the hydraulic head of ground water in aquifers
Lynn M. Highland of USGS and Peter Bobrowsky of Geological Survey of Canada, U.S. Department of the Interior, U.S. Geological Survey USGS,Circular 1325, The Landslide Handbook (a Guide to Understanding Landslides), Appendix A: Basic Information about Landslides Landslide, Part 1: Glossary of Landslide Terms, Washington, DC, USA 2013. http://pubs.usgs.gov/circ/1325/pdf/Sections/Append ixA.pdf, (ND/ Lndsld - Amer) {924}