This year I’ve been discussing methods of atmospheric divination which come under the collective heading ‘aeromancy.’ There’s been cloud divination and wind divination, but it’s reported the ancients also divined by thunder. The actual term for that is called brontoscopy.  I had trouble determining how they did it, but by chance, I recently came across some scholarly material which held the answer.  Simply put, thunder divination is calendar-based. Thunder on certain days of the year had specific meanings. I’ll start with a little background.


The lore concerning thunder divination comes to us from the Etruscans. Its original source was cited as a man named Tages, who hailed from the city now known as Tarquinia in the Lazio region of Italy. Tages wasn’t his real name, because the Etruscan language had no letter ‘G’. But Tages was the way his name was translated into Latin, so that’s the name we’ll go with.

The Etruscans were known to be great diviners and had a first-rate college of diviners who relied upon a certain religious text for making their forecasts and predictions. The brontoscopic calendar of Tages was included in the body of this religious text and consulted regularly by Etruscan diviners.