72

Caesar's blockading works. Trenches.

Quibus rebus cognitīs ex perfugis et captivis Caesar haec genera mūnītiōnis instituit. Fossam pedum xx derectis lateribus duxit, ut eius fossae solum tantundem patēret, quantum summa labra distārent; reli5 quās omnēs mūnītiōnēs ab eā fossā pedēs cccc reduxit, [id] hōc cōnsiliō, quoniam tantum esset necessāriō spatium complexus, nec facile tōtum opus corōnā mīlitum cingerētur, nē dē imprōvīsō aut noctū ad mūnītiōnēs multitudō hostium advolaret, aut interdiu tēla in noIo strōs operi destinātōs cōicere possent. Hoc intermissō spatio duas fossās xv pedēs lātās, eādem altitūdine perdūxit; quārum interiōrem campestribus āc dēmissīs locis aqua ex flumine dērīvātā complēvit. Post eas aggerem āc vallum XII pedum exstruxit; huic lōricam 15 pinnasque adiecit, grandibus cervīs ēminentibus ad commissūrās pluteōrum atque aggeris, qui ascēnsum hostium tardarent; et turrēs tōtō opere circumdedit quae pedes LXXX inter se distārent.

An elaborate system of obstructions and defenses.

73 Erat eodem tempore et materiārī et frūmentārī et 20 tantās mūnītiōnēs fieri necesse, dēminūtīs nostris copiis, quae longius ā castrīs prōgrediēbantur; āc nōn numquam opera nostra Galli temptāre atque eruptionem ex oppido pluribus portis summā vi facere cōnābantur. Quārē ad haec rūrsus opera addendum Caesar putāvit, 25 quo minōre numerō militum mūnītiōnēs dēfendī possent. Itaque truncis arborum aut admodum firmīs rāmis abscisis, atque hōrum dēlibrātīs āc praeacūtīs cacuminibus, perpetuae fossae quinōs pedes altae ducebantur. Huc illī stīpitēs dēmissi et ab infimō revinctī, nē