The Wind River Mountains display that remarkable fact which is probably familiar to our readers. Rain falling in a comparative brief area divides so that some of the drops flow westward and find their way into the Columbia and thence to the Pacific. Another part of the rainfall or melted snow winds its way ultimately to the Colorado and into the Gulf of California, while a third gropes to the Missouri and finally into the Gulf of Mexico. The southeastern part of the State, through which our friends were journeying, is drained by the North Fork of the Platte and its affluents, including the Laramie and Sweetwater rivers, the Lodge Pole, Rock, Poison Spring, Medicine Bow, Horse and Rawhide creeks. It may be added that that grand national playground known as the Yellowstone Park covers a wide area in the northwestern corner of the State.