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Land Survey Information


The land area that is now known as the State of Wisconsin was surveyed by the federal government between 1833 and 1866. The survey was done in order to divide the vast public domain into salable-sized lots that could be sold, or otherwise divested, to raise funds for the federal government and to encourage settlement. The work was done using the Public Land Survey System (PLSS), which divides land into six-mile square townships and one-mile square sections. This system was used in surveying the public domain lands of the United States beginning in eastern Ohio in 1785. The survey work was done by the General Land Office (GLO), an agency of the Treasury Department until 1849 and thereafter a part of the Interior Department. In 1946, the GLO was merged with the Grazing Service to create the modern Bureau of Land Management (BLM), which continues to have responsibility for the Public Land Survey on public domain lands. The original surveys are often referred to as the Public Land Survey or the General Land Office Survey.

The following material will provide a general description of the Public Land Survey System and instructions for how to interpret the records of the survey. There are, however, many variations and exceptions to the standard procedures found within the survey records. During the three decades that the survey was conducted in Wisconsin, the instructions to the surveyors changed and evolved. Also, the survey procedures occasionally had to be adapted in the field to meet unusual conditions. Use this information as a guide, but realize that there may be records that do not fully match the standard.

Townships, Ranges and Sections

The basic units of the public land survey are six-mile square townships that are further subdivided into one-mile square sections. Just as on a sheet of graph paper, the townships are regularly arranged across the state. The sections are further regularly arranged within the townships.

The starting point of the public land survey in Wisconsin is located on the Wisconsin - Illinois border about 10 miles east of the Mississippi. This point, known as the initial point, marks the intersection of the baseline, which is also the southern state boundary, and the principal meridian, which is a line that runs due north from the initial point. In Wisconsin, this line is known as the Fourth Principal Meridian. This line is an extension of the Fourth Principal in Illinois that has an initial point is in the west-central part of that state. The numbering of the townships in Wisconsin, however, is separate from the numbering in Illinois.

The east-west lines that cross the principal meridian every six miles are known as township lines. The north-south lines that intersect the baseline every six miles are known as range lines. The six-mile square block of land between the adjacent township lines and the two adjacent range lines is called a township.

Each township is numbered based on how far north it is located from the baseline, and how far east or west it is located from the principal meridian. For example, the city of Madison is in a township that is seven townships north of the baseline and nine ranges east of the principal meridian, thus it is in what is known as Township 7 North, Range 9 East.

Within a six-mile square township are 36 one-mile square sections. These are numbered starting with number one in the northeastern corner of the township and then moving westward with sections number 2 through 6 along the northern edge of the township with section 6 in the northwest corner. Section 7 is immediately south of section 6 and the numbering moves eastward with section 12 immediately south of section 1. Section 13 is immediately south of section 12 and the numbering then progresses westward. This back and forth pattern is repeated until reaching section 36 in the southeast corner of the township.

A note on the word township: this word is used in several different ways in this text and in other land descriptions. First and foremost it describes a six-mile square area laid out as part of the Public Land Survey System, this is also known as a congressional township because the land surveys were originally directed by congressional action, this area can also be described as a survey township. These have a numerical description such as Township 7 North, Range 9 East. The word township is also used to describe a unit of local government, a civil township. Here the name is shortened to "town" such as the Town of Vermont, the Town of Rome, or the Town of Orion. While these civil townships often share the same geographic boundaries as a congressional township, sometimes they include larger or smaller areas. To confuse the issue even further, the word township is also used to describe the east - west line of six-mile square blocks between to adjacent township lines.

Measurements and Compass Directions

The system of measurement used in the original public land survey is based on the statute mile. It is subdivided into chains and links, not feet and inches. A measuring chain is 66 feet long and there are 80 chains in a mile. Each chain is composed of 100 links each of which are 7.92 inches in length. Because there are 100 links in a chain, the measurement can be expressed as a decimal, i.e. 12.59 chains is equal to 12 chains and 59 links. To convert measurements from chains to feet, simply multiply the number of chains by 66, i.e. 12.59 chains x 66 (feet per chain) = 830.94 feet.

Compass directions used in original public land survey are based on a bearing compass rather than the azimuth, which is more commonly used today. The 360-degree circle of a bearing compass is divided into four 90 degree quadrants; northeast (equal to 0 to 90 degrees azimuth), southeast (equal to 90 to 180 degrees azimuth), southwest (equal to 180 to 270 degrees azimuth) and northwest (equal to 270 to 360 degrees azimuth). The specific direction within a quadrant is measured in degrees starting from either the north or south and moving towards either the east or west. An example of a bearing direction as written in the survey notes would be: "N 32° W." This would read "North 32 degrees West, or 32 degrees to the West of North." This would be equal to 328 degrees azimuth. Another example would be "S 64° E." This would read "South 64 degrees East, or 64 degrees to the East of South." This would equal 116 degrees azimuth.

How the work was done

The work of the Public Land Survey in Wisconsin was done under the direction of a Surveyor General who was responsible for the surveys in a large area. The earliest surveys in what is now Wisconsin were done under the direction of the Surveyor General for the states of Ohio, Indiana, and the Territory of Michigan. This office was headquartered in Cincinnati, Ohio until 1839 when it was moved to Dubuque, Iowa. At that time a new survey district was created that was responsible for the surveys of the Wisconsin Territory, which included what would become the states of Wisconsin, Iowa, Minnesota and the Dakotas from an office in what is now Dubuque, Iowa.

The actual fieldwork was done under the direction of a Deputy Surveyor. Individual Deputy Surveyors would contract with the Surveyor General for a specific area to survey. Their work was done under the terms of General Instructions, Special Instructions and Contracts. The General Instructions provided the basic procedures for how the public land surveys were to be performed. Special Instructions included specific requirements for the survey of a particular area. The contract dealt with the financial terms of the work. The Deputy Surveyor hired a crew of assistants that normally included two chainmen and an axman.

The exterior lines of the townships, the east-west township lines and the north-south range lines, were surveyed first to establish outlines of the townships. When this work was completed, a different crew of surveyors would do the work of running the section lines, or interior lines to subdivide the township into thirty-six sections. It would be convenient to think of all of the exterior township and range lines for the entire state being completed and then the interior subdivision lines were run. In reality, the exterior lines in a specific area were often completed only weeks or months before the interior lines were run.

The exterior township and range lines were run in a seemingly random fashion other than that they would complete the square outline of a township. The interior section lines, however, were run in a strict order that was rarely changed. This subdivision of a township began along the southern boundary of the township one mile west of the southeast corner of the township. This is the southern common corner of sections 35 and 36. From there the section line was run north one mile until a point was established for the common corner of sections 25, 26, 35 and 36. This line is called a true line. From that point, a line was run east between sections 25 and 36 until it encountered the range line on the eastern edge of the township. This line is called a random line. This line should meet the range line at a point previously established on the range line for the eastern common corner of sections 25 and 36. Often, however, due to slight errors in angle or measurement, the line did not intersect exactly at the point. Mathematical adjustments would be made and a new line, termed a corrected line was run back west between sections 25 and 36 until the common corner of sections 25, 26, 35 and 36 was again encountered. From there a new section line was run north one mile until a point was established for the common corner of sections 23, 24, 25 and 26. Again, a random and corrected line would be run between sections 24 and 25. This pattern was repeated until the north township line was encountered. From there the survey crew would return to the south township line and begin to run a section line north between sections 34 and 35. The procedure of running north on a true line, and then east on a random line and west on a true line was continued throughout the township until the far western line of sections where random lines were run west to the township boundary and corrected lines were run east.

In the course of the survey, permanent points were established at each corner of the square sections - known as section corners - and at the half-way point along each side of the sections - known as quarter-section corners. Quarter-section corners get their name from the fact that when these quarter-section corners on opposite sides of the section are connected with straight lines they become the corner of a quarter of a section. The section corners and quarter-section corners were marked with wooden posts, approximately four inches square and two foot tall. As reference to the section and quarter-section corners, two nearby trees - known as bearing trees - were marked with the township, range and section numbers in which they were located.

Field Notes

The work of the public land surveys was recorded in small notebooks that became the official record of the surveys. Collectively these are known as the field notes. Within an individual township notebook, there is a predictable progression of entries. Most field notebooks include the following basic entries.

Title Page

This page includes the legal description of the township being surveyed, name of the Deputy Surveyor and the dates that the work was done. Sometimes the survey crew is also listed here, and occasionally on the next page.

Sketch Map

This map was drawn in the field as part of the fieldwork.

Section Line Notes

These are the details of the work done as the surveyors ran the individual section lines. Along the left side of each page are the measured distances in chains and links. The basic entries are for the section corner and quarter-section corner. For each of these points the entry will also list the species and diameter of the bearing trees as well as the direction and distance to those trees. Other entries along the section line will include a variety of items noted by the surveyor. These include entering or leaving fields, swamps, timber or other major landscape or other vegetation types, crossing streams, or intersecting trees directly on the survey line. At the end of each section line, the surveyor wrote a brief description of the mile of line just traversed. This description included the surface of the land, the quality of the soil, the tree species along the line in order of dominance, and the undergrowth.

Meander Notes

Whenever the surveyors encountered a lake or river of significant size along the section lines, they were to set a post at the shoreline. Once these meander posts were set on all the section lines that intersected the lake or river, the shoreline was surveyed by connecting the meander corners by tangential lines.

General Description

At the end of township's survey, the surveyors wrote a general description of what they had observed during the survey of the township.


The last portion of each township is an affidavit or certificate by which the surveyor swears to have done his work properly and in compliance with the terms of his contract.

Reading the original land survey records

Be aware that the survey records can be challenging to read. These challenges come from at least three sources. First, the original survey notebooks are approximately 150 years old. During that time there has been some deterioration of the paper and fading of the inks. Second, the handwriting of the surveyors varied from a fine script to an almost unreadable scrawl. Third, the survey records are written in a shorthand manner using the terminology and abbreviations of the profession. The best advice for using this resource is to read through lots of the records to become familiar with the terminology used and the flow of the records.

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