SOME COMMON MECHANICAL MOTORS 



559 



water wheels: They can easily be changed in location. They 

 are small compared with other wheels for the amount of power 



FIG. 345. General view of the Mississippi River, the locks, the power 

 house and the dam at Keokuk. The power plant is capable of producing 

 300,000 horse-power. It cost $25,000,000. 



FIG. 346. Interior view of the power house at Keokuk showing the 15 

 generators now installed, each of which produces 10,000 horse-power of 

 electrical energy. 



they are able to produce. One such wheel constructed several 

 years ago was but 3 ft. in diameter and received its supply of 

 water from a stream 2100 ft. above the wheel. The diajneter 



