Yes, they're all bikes that belong to a friend of mine. To tell the truth I'd forgotten about the display being on and had intended to go
The 'group' is 'Bygone Bykes (Yorkshire) Club' and some members here are also members. I'm this year's Chairman. We meet every last Thursday of the month in Wakefield so if you're interested there's a meeting this coming Thursday. PM me for details.
The gear mech on the Supra is a Vittoria Marguerita which possibly predates or is contemporary with the Osgear. After each change you have to count your fingers to make sure they're all there! The technique is to twist the 'loop' at the top to move the 'prongs' on the chainstay, back pedal to guide the chain onto the sprocket you want and at the same time adjust the chain tension with the lever in the 'ratchet' frame. The owner told me that the first time he used it he wobbled about so much he hit the curb and fell off! I believe that Gino Bartali was a user of this gear and he stuck with it for a while even when better options were available.
Today is the yesterday of tomorrow.