Do you have a road named “Baseline” near your home? How about “Meridian.” When I lived near Portland, Oregon, there was a Baseline road nearby. Also, there is a Meridian, Idaho. Baseline and Meridian are terms having to do with the Public Land survey system. Public lands were divided up according to this survey system. If you look out an airplane window as you fly over the Midwest, you can actually see this division as a grid on the land.
Public Land States used the Township-Range System. For this system, 37 surveys cover 30 states. A map of the principle meridians and baselines for the US is found at the Cadastral Survey webpage as shown here. Each survey has a principle meridian line and a baseline.
- Principle Meridian (PM) = imaginary line running north and south. You can see them on this map running north to south through a state or group of states.
- Baseline = imaginary line running east and west. You can see these lines on this map running east to west through a state or group of states.
- Township = six square miles comprised of 36 sections
- Section = one square mile or 640 acres (a quarter section would be 160 acres).
Here’s how to understand the system: Each square on this grid map below represents one township. All townships are counted by their relationship to the the principle meridian and base lines. First count how many squares your township is up or down from the base line. This is your township north or south number. Then, count how many squares east or west your township is from the principle meridian line. This is your range east or west number.
For instance, the area I’ve crossed out on this map would be Township 3 South Range 4 East or T 3 S R 4 E because it is 3 townships south of the base line and four townships east of the principle meridian.
Each section may be divided up into quarters and even lots. Here are some options for dividing a section:
Given all these locators, a typical description for a public land is: “The SE 1/4 of the NW 1/4 of Section 3 Township 83 North Range 3 West of the 5th Principal Meridian comprising 40 acres.” Surprisingly, these descriptions are usually easy to plot on a map!
Later this information will come in handy as you search for deeds and then try to understand the land description within the deed. Land tract books are arranged according to the township and range numbers. They are great for spotting neighbors.
Map tools have made it easy for us to determine these numbers. The USGS is in the process of digitizing and uploading 200,000 Historic Topographic Quadrangle Maps, 1884-2006. You may see what they have posted online at the USGS Store. Once available online, you may download them for free!
Also, the county usually has maps that are gridded in this system. Those maps may be available through the county or the Family History Library.
Now that you know about the system, you’ll have a better experience working with the public land records.