Many accurate 1921 census transcriptions have already been added to the pub history site, including London, and parts of Middlesex.
Westminster St James index
The List of Masonic Lodges of 1740 - 1755 note that a masonic lodge met at the Gun, Jermain street with a constitution date of March 17th 1736
Historical London public houses, Taverns, Inns, Beer Houses and Hotels.
Residents at this address.
1736/Number 162 in seniority, Gun Tavern, Jermain street, and Constituted on Aug 24
1737/../../../Masonic Lodges 1736-39
19 January 1792/Insured: John Demay, at the Gun Tavern in Jermyn Street, tavern keeper/../../Sun Fire Insurance reords held at the LMA
1805/John Barton, coffee house keeper, 17 Jermyn street, St James's/../../Holdens Directory
1810/Thomas Murthwaite, Gun Tavern, 17 Jermyn street/../../Holdens Directory