Beginning at a point in the middle of the main channel of the Missouri River, where the prolongation north of the range line between ranges six and seven would intersect the same; thence south with said range line to the southeast corner of section thirteen, township forty-one, range seven, west; thence west with the subdivisional lines to the southwest corner of section eighteen, township forty-one, range eleven, west; thence north with the range line between ranges eleven and twelve, to its northern crossing of Profit’s Creek; thence down said creek to the middle of the main channel of the Osage River; thence down the Osage River, in the middle of the main channel thereof, to the middle of the main channel of the Missouri River; thence down the Missouri River, in the middle of the main channel thereof, to the place of beginning.