Sometimes, when searching through the catalogue (inevitably for other things), files leap out that simply have to be investigated. For instance HO 199/301 “British bombs and other devices accidentally dropped on England by British aircraft” (somewhat shamefacedly subtitled “also British mines”) does essentially what it says on the tin. But it’s an intriguing tin. However, even better is the neighbouring file from 1942, the bafflingly monikered “Journalistic astrology”. I wanted to know what journalistic astrology was. My guess was that newspaper columnists were making uncomfortably accurate predictions of military decisions but the truth is slightly stranger.