thence along said one hundred and third meridian to the thirtysecond parallel of north latitude;
thence along said thirty-second parallel to the Rio Grande, also known as the Rio Bravo del Norte, as it existed on the ninth day of September, one thousand eight hundred and fifty; thence, following the main channel of said river, as it existed on the ninth day of September, one thousand eight hundred and fifty, to the parallel of thirty-one degrees forty-seven minutes north latitude;
thence west one hundred miles to a point;
thence south to the parallel of thirty-one degrees twenty minutes north latitude;
thence along said parallel of thirty-one degrees twenty minutes, to the thirty-second meridian of longitude west from Washington;
thence along said thirty-second meridian to the thirty-seventh parallel of north latitude;
thence along said thirty-seventh parallel to the point of beginning.
