The county of Pottawatomie is bounded as follows: Commencing at the northwest corner of Jackson county; thence west with the south boundaries of Nemaha and Marshall counties, to the middle of the main channel of Big Blue river; thence down the Big Blue river, in the middle of the main channel thereof, to the middle of the main channel of the Kansas river; thence down the Kansas river, in the middle of the main channel thereof, to the second standard parallel; thence east, to the southeast corner of section thirty-five, township ten, range twelve; thence north with the west boundary of Jackson county, to the place of beginning.
K.S.A. 18-175