I found myself in the west end today which I normally try to avoid at the weekend.   It gave me time to examine the detailing on some of the houses in Brook Street at the Hanover Square end.   This is Nos. 14-16 with what Pevsner describes as ‘undercooked-looking’ terracotta:-

This is Nos.2-4, Jacobethan by C.O. Parnell:-

Next door is 21 Hanover Square, a building for the London, County and Westminster, but once the residence of Talleyrand:-