Soldiers in Napoleon's army discovered the Rosetta Stone in 1799 while digging the foundations of an addition to a fort near the town of el-Rashid (Rosetta). On Napoleon's defeat, the stone became the property of the British under the terms of the Treaty of Alexandria (1801) along with other antiquities that the French had found. Exhibited in the British Museum since 1802, the Rosetta Stone was the key to unlocking the mystery of ancient Egyptian hieroglyphs, the knowledge of which was thought to have been lost forever. The importance of this to Egyptology is immense. Soon after the end of the fourth century AD, when hieroglyphs had gone out of use, the knowledge of how to read and write them disappeared. In the early years of the nineteenth century, some 1400 years later, scholars were able to use the Greek inscription on this stone as the key to decipher them.