Miss. Code Ann. § 19-1-63

Jefferson County is bounded by beginning on the Mississippi River at the southwestern corner of Claiborne County, and thence along the southern boundary of Claiborne County to the Choctaw boundary line; thence south with said boundary to where it crosses the line between townships seven and eight; thence west on said township line to the basis meridian of the Washington district; thence north on said meridian line to the northeast corner of Adams County, at a point due east from the point being the northeast corner of where Edmond Andrews' cotton gin once was; thence due west to such point; thence westerly in a direct line to what was known and called “George Selser's Spring,” on the south branch of Fairchild's creek; thence down such south branch to Strover's mound, so-called; thence westerly in a direct line to the upper side of Rose's old settlement, on the Mississippi River; thence up said river to the beginning. The county site is Fayette.