What occurs when township lines are adjusted every fourth line?

When township lines are adjusted every fourth line, this correction is made to accommodate the spherical nature of the Earth. As the Earth is not flat, but rather a sphere, the curvature affects how land is divided into townships. In order to maintain accurate boundaries as you move further north or south, adjustments are necessary at regular intervals. This process ensures that each township remains approximately the same size and shape over vast distances, despite the Earth's shape.

This adjustment is usually done through a systematic method known as the Public Land Survey System (PLSS), which includes corrections referred to as "correction lines." These lines help to keep the townships aligned and properly defined, helping to prevent significant discrepancies that might arise due to the curvature of the Earth. The other options, while relevant to land management and property assessment, do not pertain directly to the purpose of adjusting township lines.