A point that many people mentioned amid the horror and heroism of the attack at London Bridge was the enterprising use of a narwhal tusk taken from the wall of Fishmongers’ Hall to belabour the murderous knifeman.

I am surprised to find that the first person known to use narwhal in English was good old Sir Thomas Browne, in the discussion of unicorns’ horns in his Pseudodoxia Epidemica or Vulgar Erroures, where he correctly declares that ‘those long Horns preserved as pretious rarities in many places, are but the teeth of Narhwales’.