Thank you Andy J2022 and Shaun J for taking the time to respond. Yes Shaun, the company at 35 Fenchurch Street was W. and E. James, (Gazette) wine and spirit merchant, or Wm & Edw James (P.O. Directories).
I conducted research at the Guildhall Library many years ago and found the father, Thomas, and three of his sons, William, Edward and John Hall James, in the Guild Rolls but at no point was there mention of a company name. In fact all three brothers were bankers clerks in the censuses so if the Fenchurch Street business does relate to them, I am not sure who ran it! In one of the Quarterage books in which fees paid to the Guild were entered, a personal residential address connected one of the brothers to his residential address for one of the censuses so I felt confident that these Guild members were my relatives but I am unsure how to prove that the Fenchurch address and business was theirs except by company documentation or perhaps fire insurance policies.
Thank you again for your interest.