Ebbie ~~

Good question: so I googled & found ~

"It is also called St. Stephen's Tower, a name given to the tower by Victorian journalists who also called the hall of parliament "St. Stephen's Hall". The Chapel of St. Stephen was originally built inside Westminster Palace as a private church for the king in the 13th-14th centuries (it took 70 years to complete). In 1547, parliament moved in and the chapel became the Commons Chamber. The House of Commons met there until the fire of 1834, which explains the use of the term St. Stephen's Hall as used by journalists." from 'Neatorama' website

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~M~