This question was answered recently in The Times. The newspaper’s archive editor Rose Wild writes a weekly feedback column on issues from its Letters page, and on 27^th January 2024 we were very pleased to read the following:

“I was too quick off the mark last week when I apologised for not knowing the difference between a pillar box and a letter box – at least according to an email from Michael Goodyear.

“I imagine your correspondent who complained is not aware of the Letter Box Study Group,” he writes. “A quick look at their website – lbsg.org – will tell you all about the various sorts of receptacle provided for our letters, ‘pillar boxes’ being only one type. ‘Letter box’, which you used, seems to cover them all.”

I’m indebted to Michael, not only for defending my honour but for introducing me to a new realm of arcane scholarship. This website is a gem. Never mind pillar boxes, now I can tell a wall box from a lamp box, and with further study might possibly even be able to spot a hexagonal Penfold, a George VI Type B or an Edward VII type C. Mind you, with more than 800 varieties, there’s still a way to go.

The LBSG has a serious purpose – to preserve and celebrate a category of street architecture that we’re inclined to take for granted – but it’s not all work. “Strolling and seeking unusual, undocumented, or picturesque boxes is a timeless pleasure”, it asserts, and I’m sure they’re right. If twitcher is the word for someone who collects bird sightings, should there also be a word for letter box spotter?”