John Lewis Newcastle (formerly Bainbridge) in Newcastle upon Tyne, is the world's oldest Department Store. It is still known to many of its customers as Bainbridge, despite the name change to 'John Lewis'. The Newcastle institution dates back to 1838 when Emerson Muschamp Bainbridge, aged 21, went into partnership with William Alder Dunn and opened a draper's and fashion in Market Street, Newcastle. In terms of retailing history, one of the most significant facts about the Newcastle Bainbridge shop, is that as early as 1849 weekly takings were recorded by department, making it the earliest of all department stores. This ledger survives and is kept in the John Lewis archives. John Lewis bought the Bainbridge store in 1952.
Who partnered with William Alder Dunn to open the first store? 
Emerson Muschamp Bainbridge