sentences:  Written on fragments of thin, post-card sized wooden leaf-tablets with carbon-based ink, the tablets date to the 1st and 2nd centuries AD (roughly contemporary with Hadrian's Wall).Although similar records on papyrus were known from elsewhere in the Roman Empire, wooden tablets with ink text had not been recovered until 1973, when archaeologist Robin Birley, his attention being drawn by student excavator Keith Liddell, discovered some at the site of Vindolanda, a Roman fort in northern England.The documents record official military matters as well as personal messages to and from members of the garrison of Vindolanda, their families, and their slaves.