C. Julius Caesar, Gallic War

Letters are immediately sent to Caesar by Cicero, great rewards being offered [to the messengers] if they carried them through. All these passes having been beset, those who were sent are intercepted. During the night as many as 120 towers are raised with incredible dispatch out of the timber which they had collected for the purpose of fortification: the things which seemed necessary to the work are completed. The following day the enemy, having collected far greater forces, attack the camp [and] fill up the ditch. Resistance is made by our men in the same manner as the day before; this same thing is done afterward during the remaining days. The work is carried on incessantly in the night: not even to the sick, or wounded, is opportunity given for rest: whatever things are required for resisting the assault of the next day are provided during the night: many stakes burned at the end, and a large number of mural pikes are procured: towers are built up, battlements and parapets are formed of interwoven hurdles. Cicero himself, though he was in very weak health, did not leave himself the night-time for repose, so that he was forced to spare himself by the spontaneous movement and entreaties of the soldiers.