Pyroelectricity is the ability of crystallised nonconducting materials to generate a temporary voltage when the entire crystal is heated or cooled.
Around 314 BC, the Greek philosopher Theophrastus discovered the effect when he saw that the mineral tourmaline (most probably) attracted straws and bits of wood when heated.
[ux_image_box img=”577″ image_width=”50″ link=”https://sites.google.com/a/maine207.org/economic-geology-in-the-21st-century/insulators-electrical” target=”_blank”]
Here is a statue of Theophrastus:
[ux_image_box img=”578″ image_width=”40″ link=”https://af.wikipedia.org/wiki/Theophrastos” target=”_blank”]
(circa 371 BC-circa 287 BC )