Thanks Sugarbakers. My dad worked at Tate and Lyle in Silvertown for a while whilst serving his apprenticeship. Unfortunately, those wide, flat caps remained de rigueur for several years. The ladies hats, on the other hand... Not close enough, yet. Those hats became fashionable around 1925 and remained into the 30s. We have, though, found another picture of the man who seems to be speechifying. He was indeed a Woolwich Mayor and was pictured elsewhere with the same mayor's badge - but attached to the chain. My friend is going along to the Town Hall tomorrow to photograph the regalia. The badge was a Tudor Rose with a depiction of The Great Harry on the front.