Languages die. But if they're lucky, a thousand-odd years later, someone unearths an artefact that brings them back to life.

Laura Welcher of the Rosetta Project shows us the Rosetta Disk, a slice of electroplated nickel three inches in diameter that bears text in 1500 languages for future linguists to decipher. Ilona Regulski of the British Museum describes how its namesake, the Rosetta Stone, unlocked hieroglyphics.