1816 was the ‘year of no summer’.

Volcanic ash from the Dutch East Indies

darkened Europe’s skies. Mount Tambora,

amid the savannahs of Sumbawa,

had erupted the previous year.

So June 1815 was unseasonably

wet, particularly in Belgium.

Escaped from Elba, Bonaparte had rallied

France, almost expunging Blucher’s Prussians

in Wallonia. At Waterloo,

on the morning of the 8th, Napoleon –

once begetter of Le Code Civil

Des Français before he crowned himself –

waited for the ground to dry in order

to deploy his cavalry to best effect.

However, Blucher’s remnants joined Wellington’s

‘scum of the earth’, and Boney rode from the field

in tears. His ‘critical error’ became

part of the military syllabus.

Add choice and pride to physics and chance

butterflies too can make a right mess of things.