How does the rectangular survey system work?

The rectangular survey system, also called the government survey system, divides land using a grid of principal meridians running north-south and base lines running east-west. The grid creates six-mile-square townships, each containing 36 one-mile-square sections of 640 acres. Townships are identified by their row and column position relative to the meridian and base line using township and range numbers. Sections are numbered one through 36 in a serpentine pattern starting from the northeast corner.