Thank you for the insider knowledge & clarifications. For a long time here in AU we had metric on many items with imperial measurements in parenthesis, but it'

Thank you for the insider knowledge & clarifications. For a long time here in AU we had metric on many items with imperial measurements in parenthesis, but it's rare to see that now (except on retail-packaged foodstuffs imported from the UK, and perhaps the US). Car engine displacement -- I can't find a good explanation of when that preference may have changed for the USA. I'm aware that 1959 marked the alignment of the British vs USA inch, but I believe the difference was tiny (enough to annoy you if you'd just purchased some very fine feeler gauges, but not enough to noticeably change the engine displacement measurement). It sounds like it may simply be a reaction to car manufacturers describing displacement in litres - and so may be a consequence of the shift in ownership from domestic to foreign (metric marketed) cars. A friend of mine renovates very old cars - he's doing up a Riley at the moment, and was describing the variations on Whitworth (and others) to me. Of particular delight was his describing the subtle change to the bolt heads during the 1940's. The Wikipedia page for Whitworth Standard [1] summarises it well (though I can't but help feel that no one involved in these specifications genuinely understood the meaning of the word Standard). Quoting from same: "However, in World War II the size of the Whitworth hexagon was reduced to the same size as the equivalent BSF hexagon purely to save metal during the war and they never went back to the old sizes afterwards." A lovely segue to another HN article earlier today about skeuomorphic designs that linger like a bad smell. I'm danged happy to have grown up in a society that embraces metric. [1] https://en.wikipedia.org/wiki/British_Standard_Whitworth https://en.wikipedia.org/wiki/British_Standard_Whitworth