I take issue with Peter Walker on the route of the CITY CIRCLE 19 as I do not remember it ever going to Five Ways were it would have met the INNER CIRCLE. My memory is that it crossed Broad St from Granville St to Sheepcote St.
That's what I thought as well. Here's an extract from my (incomplete, only done to wartime yet!) BCT route database:
2/3/1932 New service
19 Benacre St, Bristol St, Great Colmore St, Cregoe St, Granville St, Broad St, Sheepcote St, St Vincent St, Summer Hill St, Powell St, Albion St, Frederick St, Vyse St, Well St, New John St, Aston Rd, Dartmouth St, Lawley St, Watery Lane, Adderley St, High St Bordesley, Alcester St, Vaughton St and Gooch St to Benacre St. Service named “City Circle”.
25/9/1939 Wartime restrictions: Service operates weekday peak hours only.
19/7/1943 Service diverted from Benacre Street via Sherlock Street, Gooch Street and Wrentham Street to Bristol Road.