Hearing a Radio 4 play last week about the Cornish scientist Humphry Davy and his research into nitrous oxide ("laughing gas") reminded me of the moment, many years ago, when I turned on the radio and caught the tail end of a song about Humphry Davy being sung with great exuberance by a singer I took to be another great Cornish celebrity, Brenda Wootton. This was so long ago and so fleetingly brief that I can remember nothing about it except that it had a very lively tune and the refrain mentioned laughing gas (I think!). It's become one of those mental maggots that not even Google can resolve so can anyone tell me if Brenda Wootton really did sing a song about HD, did she record it, and does anyone have the words and melody?