8o The Drainage of Fens and Low Lands. 



supplies the place of the self-acting doors placed across the 

 outlet. The wheel for draining the Morton Car district in 

 the Trent has been fitted with this arrangement Mr. 

 Naylor also included in his patent a curved guide for caus- 

 ing the water to enter at the under side of the wheel, so 

 that the scoops should not " come in contact with the water 

 until they have ceased to descend, and are travelling hori- 

 zontally, or nearly so, on the under side of the axis." The 

 blades or arms in the wheel are curved backwards, or in the 

 opposite direction to that in which the wheel revolves, so 

 that the water may leave them advantageously on the rising 

 side of the wheel. 



The wheels at Katwijk, in Holland, have been fitted with 

 a somewhat similar arrangement to that here described, the 

 floor in front of the wheels being movable, and hung on 

 hinges, so that it can rise up automatically, and form an 

 adjustable breast, suitable to the vaiying level of the water 

 in the outlet. 



Very few of the old wheels have been fitted with shuttles 

 to regulate the supply of water to the scoops. With a vary- 

 ing height of water it is not possible, without this arrange- 

 ment, to work the wheel to the best advantage. By means 

 of the shuttle the depth of immersion of the scoops can be 

 controlled, and the wheel prevented from being overloaded. 

 The shuttle is also useful in adjusting the load either at 

 first starting, before the wheel has got into full swing, or, in 

 the case of a tidal outfall, in diminishing the supply to the 

 wheel as the height of lift increases with the rise of the tide. 

 The shuttle consists of a wooden framework, with a sliding 

 door fitted in the raceway close up to the wheel, sloping at 

 such an angle as to be tangential to the circumference of 

 the wheel. The door is provided with friction rollers, which 

 work on a frame in the side next the wheel, and is provided 

 with a balance weight and rack and pinion for moving and 

 adjusting the shuttle. A shaft can be carried into the 



