Did you know? Height of St Paul's Cathedral in London (111 m) is 500 x Length of a standard DL business envelope (220 mm)
Diameter of US dollar coin (26.5 mm)
/fact/diameter-of-us-dollar-coin
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Yes, there's now a book based on these numbers. Oxford University Press: July 2018.
Click here to learn more about it.
Click here for Podcast: Andrew Elliott interviewed for New Books Network.