thanks Chris - and agree this is a very good design, which may well have gone all the way through to the 1957 catalogue - but you will know better than me on that point
I particularly like the 'double line effect' that the threading produces when viewed from above - very attractive. Anyway, thanks for the confirmation, which appreciated. Is that a W/Fs. stem vase next to the swan? I don't have time to read the original link this evening, so will look properly tomorrow. thanks again.