Three noteworthy shadows

Peter Schlemihl allowing his shadow to be cut off. Etching by George Cruikshank, 1823

Peter Schlemihl's Wundersame Geschichte by Adelbert von Chamisso

Shadows that never stop moving
Once shadows were created by the sun, the moon, candles and gas-lamps. These veteran shadows moved, continually. They never ceased their motion: edging almost unnoticed from one space to another, or trembling and shivering across walls and ceilings. In contrast, modern shadows are static: electric bulbs have made sure of that.

Shadow merchants
Reputedly in Transylvania in ancient times, a live person was laid beneath the the foundation stone of a new building or sealed into the walls to guarantee that a ghost would haunt the building and therefore protect it from any hopeful thieves. More recently (and up until the end of the nineteenth century) this ritual has been replaced with a new tradition: that of burying the shadow - or the length of the shadow of a passerby - who would then as a result die within forty days (or at least within a year). A shadow merchant would measure other people's shadows and then make them available to the architect.

Shadows and walls
In Hiroshima a different sort of shadow manifested itself on the wall of a bank. Half a kilometer from the atomic blast, a man who was waiting for the bank to open, momentarily blocked the wall from the wave of heat that assaulted the city. That brief instant was enough time for the vestiges of his form to be left indelibly on the surface.

For more about shadows, have a look at Shadows: Unlocking their secrets, from Plato to our time, Roberto Casati, Vintage 2004.