:’) And there’s that Etruscan pottery...
The position of the ancient vases during firing is known. They were fired in a standing position, as the flow of the glaze testifies. The magnetic inclination or the magnetic dip of the iron particles in the fired clay indicates which was the nearest magnetic pole, the south or the north...
...show that the magnetic field of the earth...was disturbed sometime during or immediately following the eighth century to the extent of complete reversal...