Redundant

A symbol of redundancy on a site of redundancy on a day of redundancy.
This Ring and Balls sculpture in front of the former power station at Cockenzie  (closed last month -  March 17 blip)  is on the site of a former coal mine.  So not only were the former coalminers made redundant and more recently the power workers but it was announced today that almost 600 coalworkers  are to be made redundant by Scottish Coal.  
A board nearby says
To improve combustion, the coal burnt at Cockenzie has to be crushed  into a very fine powder prior to being blown into one of its 4 boilers.  To achieve this, each boiler is fed by 6 pulverised  Fuel Mills, and each mill contains a top and bottom grinding ring, and 10 grinding balls.  The grinding balls are sandwiched between the two grinding rings and are spun at the rate of 37rpm, crushing coal as they go.
The grinding ring and balls that you see here processed approximately 500,000 tonnes of coal in their lifetime.  This in turn generated around 12 million million watt hours of electricity, enough  to supply every home in Edinburgh with electricity for around 10 years.