196 Nature's Piracies. 



the turbine itself, which is able to move the 

 water-gate in either direction according as 

 the balls rise or fall. For instance, if the balls 

 rise beyond their normal position, it shows 

 that the dynamo is increasing in speed, and 

 immediately machinery is brought into action 

 that shuts the water off in a small degree, just 

 enough to bring the speed back to normal. If 

 the balls drop to any extent, it shows that the 

 load is too great for the amount of water, and 

 that the dynamo is decreasing in speed; im- 

 mediately the power is brought into action, 

 now in the opposite direction, and the water- 

 gate is opened wider. These slight variations 

 of speed are constantly going on, and the con- 

 stant opening and closing of the gate follows 

 with them. It is a beautiful piece of ma- 

 chinery, and is beautifully adapted to the 

 work it has to perform. It is continually 

 standing guard over this greater piece of 

 machinery that is exerting an energy of 5000 

 horse-power and prevents it from going wrong, 

 both in doing " that which it should not do 

 and leaving undone that which it should do." 

 It is a machine that, when in action, points a 

 moral to every thinking person who beholds it. 

 Every man has such a governor if he only has 

 the inclination to use it. 



I have said further back that the water- 

 head varies, but usually at long periods. This 

 variation is chiefly caused by changes of 



