I think I might have found Anne's bowl:
<photo edited out until permission granted>
Mould 450, 16th September, 1950.
I recently came across an article about Century Glass, who were based in Edmonton, London. I was only really skimming it until I saw this pic (above) and thought 'Hmm...I recognise that...'
'Century Glass was a previously unknown Glasshouse, until a ledger was donated to the Shipley Art Gallery in Gateshead. The spine was labelled Century Glass, and from the Pottery Gazette Reference book of 1956, this was identified as the trade name of the Century Glassworks Ltd. based at the Angel Factory Colony, Angel Road, Edmonton'.
I do have more information, but feel unsure about whether I can crib someones article onto this forum. :?