RCW 36.04.320: Spokane county.

Spokane county shall consist of the territory bounded as follows, to wit: Commencing at the northeast corner of Lincoln county; thence up the midchannel of the Spokane river to the Little Spokane river; thence north to the township line between townships twenty-nine and thirty; thence east to the boundary line between Washington and Idaho; thence south on said boundary line to the fifth standard parallel; thence west on said parallel to the Colville Guide Meridian; thence north on said meridian to the place of beginning.