Knowledge of Vulgar Latin comes from a variety of sources. First, the comparative method reconstructs items of the mother language from the attested Romance languages. Also, prescriptive grammar texts from the Late Latin period condemn some usages as errors, providing insight into how Latin was actually spoken. The solecisms and non-Classical usages occasionally found in late Latin texts also shed light on the spoken language. A windfall source lies in the chance finds of wax tablets such as those found at Vindolanda on Hadrian's Wall. The Roman cursive script was used on these tablets.