George Monbiot coins the word “perceptionware” for technology trailed but never trialled, and only intended to impress the credulous (The expansion of Heathrow would be an expensive disaster for Britain and the world. Burnham needs to block it, 3 October). But the IT industry has long had a word for this: “vapourware” – which seems apt when discussing aircraft emissions.
Robin Hughes
Worrall, South Yorkshire
• In the 1960s, my friend Linda shared a room in Paddington, London, with her friend Cynthia. Two beds in the living room, a kitchen and a shared bathroom. Normal in those days. If I went there for supper, Cynthia would get undressed and into bed at 9pm on the dot. It was difficult not to get the hint, with her head on the pillow and her eyes screwed shut. I went home (Letters, 4 October).
Mary Finch
Ditteridge, Wiltshire
