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Parliamentary constituency in the United Kingdom, 1832–1885
Under original proposals it would have been greater, taking all of Dulwich and Brixton and possibly two parishes to the east. The commissioners appointed to fix parliamentary boundaries attempted to equalise the seven new "metropolitan" constituencies of London in number of voters and in population. For this reason Bermondsey and Rotherhithe were assigned to Southwark. It was also decided not to include the entirety of the parishes of Camberwell and Lambeth: both were very large parishes running five or six miles south from the Thames. The portions closest to the river were heavily built up, but the southern sections were mainly rural. Dulwich and part of Brixton were therefore excluded, instead forming part of East Surrey.
"From the Point at which the Road from London to Dulwich by Red Post Hill leaves the Road from London over Herne Hill in a straight Line to Saint Matthews Church at Brixton; thence in a straight Line to a Point in the Boundary between the respective Parishes of Lambeth and Clapham One hundred and fifty Yards South of the Middle of the Carriageway along Acre Lane." Britain, Great (1832). The statutes of the United Kingdom of Great Britain and Ireland, Vol.72. London. p. 360. Retrieved 12 August 2012.