One of four existing copies of the 1297 Magna Carta. Credit: National Archives & Records Administration
From Live Science:
The Magna Carta helped form the foundation for modern English and U.S. law. Now one of two copies known to exist outside England is headed for a special new case to preserve it.
The very first Magna Carta dates to 1215, when English barons forced King John to write down the traditional rights and liberties of the country's free persons. A copy of the Magna Carta signed by King Edward I in 1297 currently resides within a helium-filled casement at the National Archives Building in Washington. But the medieval document is scheduled for a temporary removal in 2011 so it can be re-measured for a new case filled with argon.
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