Fla. Stat. § 6.08

The line commencing on the Chattahoochee River near a place known as “Irwin’s Mills,” and running west to the Perdido, marked throughout by blazes on the trees, and also by mounds of earth thrown upon the line, at distances of 1 mile, more or less, from each other, and commonly known as the “Mound line” or “Ellicott’s line,” and by these names distinguished from another line above, running irregularly at different distances not exceeding one and a half miles from the “Mound line” and marked by blazes only, and known as the “Upper line,” or “Coffee’s line,” is the boundary line between the States of Florida and Alabama.