For a complete glossary, please see the General Land Office Website.

Brief Glossary

Base Line 

The true east-west line (on a parallel of latitude) extending from an initial point in both directions. From this line are initiated other lines for the Cadastral Survey of the public lands, within the area covered by the principal meridian that runs through the same initial point.

Issue Date 

The month, day, and year that the President signed the land document. On this document you will also find signatures of officers or employees of the GLO. Beginning June 17, 1948, the authority was delegated to the Secretary of the Interior to issue patents on public lands.


 Principal Meridian 

The true north and south line extending from an initial point in both directions. Principal meridians are the first north-south lines (meridians) surveyed for an area and form the basis for measuring ranges east and west. Principal meridians used within each state can have numeric names such as "Fifth Principal Meridian" or common names such as "Chocktaw Meridian." Some states have more than one principal meridian, for example, Arkansas has the Fifth Principal Meridian, and Mississippi has five principal meridians: Chickasaw, Choctaw, Huntsville, St. Stephens and Washington.



A row or tier of townships lying east or west of the principal meridian and numbered successively to the east and to the west from the principal meridian.



Range Direction 

The Range Direction indicates which side of the principal meridian the township is on. In the example "Township 5 North, Range 12 West," West indicates the direction of the township from the (vertical) meridian. Range directions can be either east or west.


Range Number

A Range Number identifies a township's East or West relation to its principal meridian. In the example "Township 5 North, Range 12 West," the number 12 represents the Range Number used to identify the township that is 12 tiers to the left of the principal meridian.


A section is a regular tract of land, 1-mile square, containing 640 acres, within a township. It is approximately 1/36 of a township.


Section Number

Identifies a section within a township. Sections are usually numbered 1 to 36 but can be higher in some states. Alphabetic characters may be included in the section number. In some instances there are surveys with duplicate section numbers that are identified by a numeric-alpha (e.g., 12 or 12U). 



A township is a major subdivision of the public lands under the rectangular system of surveys. It is a tract of land contained within the boundaries of the north-south range lines. Most townships are 4-sided, measuring approximately 6 miles on each side and containing approximately 36 square miles, or 23,040 acres.


Township Direction 

The Township Direction indicates which side (north or south) of the baseline the township is on. In the example, Township 5 North, Range 12 West," North indicates the Township Direction from the (horizontal) baseline.



Township Number 

A township number is identified by its relation to a base line and a principal meridian. For example, "Township 5 North, Range 12 West" identifies a particular township that is 5 tiers up from the base line. In this example, the number 5 represents the Township Number. Some townships may be fractional.