Division bell

A division bell is a bell rung in or around a parliament to signal a division and thus call all members of the chamber so affected to vote in it.

The bell is used in the immediate neighbourhood of Palace of Westminster (which houses Parliament) to signal that a division is occurring and that members of the House of Commons or of the House of Lords have eight minutes to get to their chosen Division lobby to vote for or against the resolution. The call for a division is also displayed on the Annunciator screens throughout the Palace of Westminster. The division bells are also sounded at the point when the house sits (at the start of its day); at the end of the two-minute prayers that start each day and when the house rises. There are approximately five hundred bells in and around the Palace of Westminster.

As some Members may be in nearby offices, restaurants, pubs or shops, some of these have their own division bells connected to those in the Houses of Parliament; others will use a system of pagers co-ordinated by the Whip's office of each party.

The headquarters of the major parties are all within reach of the division bell, and this area roughly defines the geographical limits of the Westminster Bubble.

Though the Commons and Lords share division bells, they are driven from separate ringing generator systems which means that the bells make a noticeably different sound for a division of the House of Commons and a division of the House of Lords.

The generator for the House of Commons simultaneously sounds all the division bells with a 2 Hertz signal for exactly eight minutes. As soon as the bells stop, the door keepers manning the entrances to the two division lobbies close and lock the doors. Any MP who has failed to enter the lobby in time has lost the ability to vote in that division.

A broadcast of the BBC's Antiques Roadshow in October 2007 from the Banqueting House in Whitehall featured the original Ringing Generator System Number 1 from the House of Commons. The programme's expert, Paul Atterbury, with the help of former House of Commons Speaker Baroness Betty Boothroyd, demonstrated the apparatus in use with one of the original Division Bells. The show valued the transmitter at £15,000.

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