APPLICATIONS OF THE RUNNING WATERS. 



39 



of the Mullau road first came into the country the forest was in the 

 main intact. Tlie extreme rise in the St. Mary and the North Fork 

 seldom exceeds 2 or 2.5 meters (G.5 to 8.2 feet). 



The principal applications of the water in the streams, not consider- 

 ing the item of navigation, are in the mining and lumbering indus- 

 tries, such as famishing motive power for ore-concentrating plants 

 and sawmills, and means for logging, placer mining, and irrigation. 

 The principal streams whose waters are used by the concentrating 

 plants are the South Fork and Canyon ("reek, one of its feeders. 

 Fart of the water appropriated by them furnishes motive power; 

 part of it is employed to effect the separation of the metallic part 

 of the ores from the lighter gangue. After it is used the water is 

 of course returned to its channel. Lt is then heavily charged with 

 the siliceous slimes derived from the crushed gangue of the ore, 

 and more or less of the metallic elements which the concentrating 

 machinery failed to save, such as the sulphides of lead, iron, antimony, 

 zinc, and arsenic in various combinations. The color of the slime-laden 

 water is a dirty gray, and the particles held in suspension are deposited 

 along its course. Undoubtedly some of the metallic elements enter into 

 the water in a state of solution after exposure to the action of moisture 

 and air. After passing through these establishments the water is unfit 

 for either drinking or irrigation purposes. Most of the matter held in 

 suspension is deposited in the calm slack-water portion and little, if any, 

 reaches Lake Occur d'Alene. So far as I know, no deleterious substance 

 attributable to the concentrators has been detected in the Spokane 

 liiver. As the water supply of the city of Spokane is taken from this 

 river, the question whether any of the slimes suspended or dissolved 

 pass through Lake Cceur d'Alene into the Spokane is of some importance. 



MILLING AND LOGGING. 



The water is little, if at all, used as motive power for the sawmills at the 

 present time. Steam is now very generally employed for this purpose. 



For logging, the North Fork, Cuuir d'Alene, St. Joseph, and Lake 

 Cceur d'Alene are utilized. The stage of water does not permit general 

 driving in the North Fork and upper and middle St. Joseph above the 

 head of navigation except during and for a short time after the annual 

 freshets. The St. Mary would afford water high enough in the spring 

 for this purpose were it not for the obstruction of rocks aud its tortuous 

 channel in the canyon where it breaks through the basaltic outflows. 

 This is about or 8 kilometers (3A to 5 miles) in length. Attempts have 

 been made to pass logs through this canyon, but they have always 

 failed. Logs can be floated down the North Fork for a distance of at 

 least 80 kilometers (50 miles) above its mouth by taking advantage of 

 its highest stage of water. Two of its tributaries, the Little North 

 Fork and another unnamed stream of equal volume, have water deep 



