The Rosetta Stone was the key that unlocked the mysteries of Egyptian hieroglyphics. Napoleon's troops discovered it in 1799 near the seaside town of Rosetta in lower Egypt, and it eventually made its way into the British Museum in London where it resides today. It is a slab of black basalt dating from 196 BC. inscribed by the ancient Egyptians with a royal decree praising their king Ptolemy V. The inscription is written on the stone three times, once in hieroglyphic, once in demotic, and once in Greek. Thomas Young, a British physicist, and Jean Francois Champollion, a French Egyptologist, collaborated to decipher the hieroglyphic and demotic texts by comparing them with the known Greek text. From this meager starting point a generation of Egyptologists eventually managed to read most everything that remains of the Egyptians' ancient writings.