CHAPTEK XVII. 



METHOD OF MEASURING WATER FOR 

 GENERATING POWER. 



THE accurate measurement of the water flowing 

 down a stream is sometimes a matter of con- 

 siderable difficulty, but a moderately close 

 approximation may generally be obtained by 

 one of the following methods. 



In a Running Stream. 

 Choosing a part of the stream where the 

 section is fairly regular, mark off a convenient 

 distance, say 20 yards, along the bank. Then 

 throw a float (a bottle sunk down to the cork 

 makes a very good float) into the stream, and 

 see how long it takes to travel the distance set 

 out. The experiment should be made two or 

 three times, and the average speed recorded. 

 The speed thus measured is that of the surface 



