It is powered by an engine which drives a hydraulic pump to send oil under high pressure around its plumbing in order to animate its limbs.

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General scepticism about OPEC's ability to pump any more oil has also put upward pressure on the price.

ECONOMIST: Pumping all they can? | The

Too many wells release the natural pressure in the field, like fizz from a soda can, and it becomes too expensive to pump the oil out.

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