The earliest known evidence for ancient knowledge of magnetism is the writing of the sixth century BCE Greek philosopher Thales of Miletus, who described the attraction between a magnetite-rich lodestone and fragments of iron. However, there is some circumstantial evidence that an understanding of magnetism existed in Mesoamerica before even then: a magnetized bar unearthed at the Olmec site of San Lorenzo in southern Mexico has been dated to 1400-1000 BCE; a strong magnetic anomaly on the snout of an … Continue reading Ancient Mesoamerican Sculptures Found to Intentionally Incorporate Magnetism