Article 2, Section 3. Boundaries of the state
The limits and boundaries of the state of Mississippi are as follows, to-wit: Beginning on the Mississippi river (meaning thereby the center of said river or thread of the stream) where the southern boundary line of the state of Tennessee strikes the same, as run bv B. A. Ludlow, D. W. Connelly, and W. Petrie, commissioners appointed for that purpose on the part of the state of Mississippi, A. D., 1837, and J. D. Graham and Austin Miller, commissioners appointed for that purpose on the part of the state of Tennessee; thence east along the said boundary line of the state of Tennessee to a point on the west bank of the Tennessee river, six four-pole chains south of and above the mouth of Yellow creek; thence up the said river to the mouth of Bear creek; thence by a direct line to what was formerly the northwest corner of the county of Washington, Alabama; thence on a direct line to a point ten miles east of the Pascagoula river on the Gulf of Mexico; thence westwardly, including all the islands within six leagues of the shore, to the most eastern junction of the Pearl river with Lake Borgne; thence up said Pearl river to the thirty-first degree of north latitude; thence west along said degree of latitude to the middle or thread of the stream of the Mississippi river; thence up the middle of the Mississippi river, or thread of the stream, to the place of beginning, including all islands lying east of the thread of the stream of said river, and also including all lands which were at any time heretofore a part of the state.
SOURCES: Preamble, const. 1817.