There is also disturbing evidence that the weakness in the so-called periphery countries has spread to the 'core' - not just France, where the index reflecting new manufacturing orders fell to its lowest level since 2009, but also to Germany.

BBC: No quick fix for Euro - maybe a slow one?

What it does is, Owen argues, leave the periphery floundering while over-pressuring the core economies.

BBC: Tick, tock: The risks of depositor flight in Greece

Britain used to fear languishing on the EU periphery while a core of true believers raced towards ever-closer union.

ECONOMIST: Britain and Europe: No laughing matter | The

But optimists argue that the scale of the bond-market moves and the dynamics behind them are totally different in the core and in the periphery.

ECONOMIST: Get ready for more volatility in government bonds

But in the United States, and much of the rest of the high-income world, this is accomplished by bringing residents from the periphery to the core by car, train, bus and increasingly through telecommunications, even as most jobs are located elsewhere in the urban area.

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