de bello gallico, 1.5

After his death, the less by none, the Helvetii tried to do this which they had decided, to leave from their territory. When now they thought that were prepared for this thing, they burned all their cities, numbering to twelve, their villages, numbering to four hundred, and the remaining private buildings; they torch all the grain, except that which they would carry with them, so that, with the hope of returning home having been removed, they were more prepared for every danger about to be undertaken; they order each one to carry from home ground grain for three months. They persuaded the Raurici and the Tulingi and the Latovici, their neighbors, having used the same plan, their cities and their villages having been burned, to set out together with them, and they took the Boii (who had lived across the Rhenus and had gone across into the Noric territory and had attacked the Noreia) to themselves, having been received to themselves as allies.