CONVERSION OF POWER INTO LIGHT, ETC. 3! 



animal motive-power, may all be converted into 

 electrical light and heat by being applied to turn 

 magneto-electric machines, such as are used 

 in modern lighthouses to illumine dark seas and 

 headlands with the splendor of sunshine. The 

 mechanical force of the rise and fall of the tides 

 on sea-coasts is adequate to rotate a sufficient 

 number of magneto-electric machines to illumi- 

 nate all the bordering shores ; and that of the 

 waters of Niagara to illumine the great cities of 

 the world. 



