Early machines used flywheels to stabilize their motion and had complex systems of gears and levers to control the machine and the piece being worked on.

But the local phone companies have always controlled the most crucial last piece of the network - the so-called tail that carries traffic from the long-distance network to a company's front door.

Time Warner controls the most profitable piece of New York's cable market, Manhattan, so it has also been mentioned as a possible acquirer.

Down in those churning sandy depths lie wells of color with their roots embedded in the hidden mechanisms that control the piece.

Aztar, which is based in Phoenix, controls the last piece of land on the Las Vegas Strip that can be developed into a casino resort.

Mr. Lazovic said the skeptics also included Selim Beslagic, the powerful Mayor of Tuzla, who now controls the largest piece of territory still in Muslim hands in Bosnia and Herzegovina and who has joined the delegation in Geneva.

Morris' ambitions are all on the surface, and you could see that he wanted to crack into Slate and control the piece.

This shows who controls the piece during play.