11.29Windmill
These are a distinctive feature of the Australian landscape. They are very useful for drawing water from wells. This one has a wooden shaft running through wooden guides, meaning that repair is cheap and can be done by people with limited access to specialised tools.
A leather washer/metal valve and metal piston assembly is in the bottom of the pipe, which goes down into the ground. The piston valve closes and lifts water through the footvalve below it, and lifts up the water column above the piston every time the windmill above revolves. On the second half of the stroke, the footvalve closes, the piston valve opens, and the piston moves down, more water passing through its valve, ready to lift more water. The water is usually lifted to an above ground galvanised iron or concrete or plastic tank.
The blades are kept turned into the wind by the rudder or tail behind. When repairs are needed, or in very strong winds, the windmill blades can be turned so that they are not affected by the wind, usually by adjustment of the position of the rudder.
GPS S 30.99341° E 151.67302° Walcha S 30.99497° E 151.67213°
Walcha Grid Reference 732.2 701.99