Many accurate 1921 census transcriptions have already been added to the pub history site, including London, and parts of Middlesex. If you can contribute to the site, send me some details to Kevan, along with some description of the specific property.
Cripplegate pub history index
There is a beer house which existed from at least 1851. There is a beer house at the intersection with Figtree Court. At 18 Barbican in 1869, there is a beerhouse at the same intersection.
Historical London public houses, Taverns, Inns, Beer Houses and Hotels.
Residents at this address.
1851/George Knowles/Beer Shop Keeper/30/Bromley, Kent/Census
1851/Mary Ann Knowles/Wife/30/Bromley, Kent/Census
1851/John G Knowles/Son/8 months/Mitcham, Surrey/Census
1856/Samuel Griffin/Beer Retailer/../../Post Office Directory
1860/Samuel Griffin senior/Beer Retailer/../../Post Office Directory
1864/Samuel Griffin senior/Beer Retailer/../../Post Office Directory
1869/George Bedwell/Beer Retailer/../../Post Office Directory