70 PHYSICAL GEOGRAPHY. 



CHAPTER VI. 



DRAINAGE OF NEBRASKA AND CHARACTER OF 



ITS WATER. 



General Character of the Drainage Character of the Water Source of 

 Impurities Character of the River Water Temperature of the Missouri 

 River Water Water of the Platte, Republican and Bow Rivers. 



GENERAL CHARACTER OF THE DRAINAGE. 



FROM the preceding presentation of facts, and the discussions 

 concerning them, it is clear that the drainage system of Ne- 

 braska is complete. The State, as a whole, slopes eastward, and a 

 little southward. There is little flat land. The great body of the 

 State varies from a very gently, almost imperceptibly rolling region, 

 to one that is made up of rounded, hill-like masses, with long, gentle 

 slopes. The subsoil is the best in the world for drainage, being 

 made up principally of Loess materials, and, where these run out, 

 is composed of Alluvium, or Drift. The Loess contains eighty 

 per cent, of finely comminuted silica, and as this deposit is of enor- 

 mous average thickness, it absorbs excessive rainfall like a sponge. 

 The Alluvium also contains a large amount of silica, and the Drift 

 is noted for that material. The average elevation of the whole 

 State is about 2,312 feet above the sea. In the lay of the land, 

 therefore, its physical character, its slope, and elevation above the 

 sea, it is in the best possible condition for perfect drainage. It is 

 owing to this combination of causes that farmers are seldom, in the 

 wettest weather, delayed more than a day or two in plowing. In 

 fact, as soon as the rain ceases, in most soils, they can plow with- 

 out injury to the land. It is also owing to these causes that Ne- 

 braska possesses such admirable natural roads. Twelve hours after 

 the heaviest rains the roads are comparatively dry. It is true that 

 roads that cross creek bottoms are sometimes an exception ; and 

 this is because occasionally there are longer or shorter distances 

 here that are underlaid with strata of clayey material. Here the 



