Fourth principal meridian

U.S. Bureau of Land Management map showing the principal meridians of Ohio, Indiana, and Illinois

The fourth principal meridian, set in 1815,[1] is the principal meridian for land surveys in northwestern Illinois and west-central Illinois,[2] and its 1831[3] extension is the principal meridian for land surveys in Wisconsin and northeastern Minnesota.[1][2] It is part of the Public Land Survey System that covers most of the United States.

The fourth principal meridian begins at a point on the west bank of the Illinois River in Schuyler County, Illinois. The fourth principal meridian's baseline, sometimes called the Beardstown baseline, runs west from this initial point.[1][2] The meridian and this baseline governs surveys in Illinois that are west of both the Illinois River and the third principal meridian.[2]

The Illinois Department of Transportation 2003 Survey Manual gives the point as 40°0′50″N 90°27′11″W / 40.01389°N 90.45306°WCoordinates: 40°0′50″N 90°27′11″W / 40.01389°N 90.45306°W and notes that the meridian is an extension of the line north from the mouth of the Illinois River near Grafton, Illinois.[1]

Extended

The meridian was extended north in 1831, through Wisconsin and northeastern Minnesota.[3] The extension uses the Illinois–Wisconsin border as its baseline,[1][2] and is the basis of surveys in all of Wisconsin, as well as that part of Minnesota:

The initial point of the extended fourth principal meridian is located at 42°30′27″N 90°25′37″W / 42.50750°N 90.42694°W.

See also

References

  1. 1.0 1.1 1.2 1.3 1.4 "Chapter Five: Land Surveying". Survey Manual. Springfield, Illinois: Illinois Department of Transportation, Bureau of Design and Environment. 2003-02-28. p. 5–5. Retrieved 2008-10-30.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Raymond, William Galt (1914). Plane Surveying for Use in the Classroom and Field (via Google Books) (2nd edition ed.). New York: American Book Company. p. 456.
  3. 3.0 3.1 "Part 5: Public Land Survey System". National Mapping Program Technical Instructions: Standards for USGS and USDA Forest Service Single Edition Quadrangle Maps (Draft for Implementation ed.). March 2003. pp. 5A–25A–4. Retrieved 2008-10-31.
  4. Minnesota Geospatial Information Office http://www.mngeo.state.mn.us/glo/Index.htm

External links