Quō praeceptō ab eīs dīligentissimē observātō, cum quaepiam cohors ex orbe excesserat atque impetum fēcerat, hostēs vēlōcissimē refugiēbant. Interim eam partem nūdārī necesse erat et ab latere apertō tēla recipī. Rūrsus cum in eum locum unde erant ēgressī revertī coeperant, et ab eīs quī cesserant et ab eīs quī proximī steterant circumveniēbantur. Sīn autem locum tenēre vellent, nec virtūtī locus relinquēbātur neque ab tantā multitūdine coniecta tēla cōnfertī vītāre poterant. Tamen tot incommodīs cōnflīctātī, multīs vulneribus acceptīs resistēbant et māgnā parte diēī cōnsūmptā, cum ā prīmā lūce ad hōram octāvam pūgnārētur, nihil quod ipsīs esset indīgnum committēbant. Tum T. Balventiō, quī superiōre annō prīmum pīlum dūxerat, virō fortī et māgnae auctōritātis, utrumque femur trāgulā trāicitur; Q. Lūcānius ēiusdem ōrdinis, fortissimē pūgnāns, dum circumventō fīliō subvenit, interficitur; L. Cotta lēgātus omnēs cohortēs ōrdinēsque adhortāns in adversum ōs fundā vulnerātur.
notes
Ambiorix's forces attack the column in a defile.
Quo praecepto...observato: ablative absolute. Quo is connecting relative (Gaisser) ( A&G 308.f).
ab latere aperto: 'on their open flank;' the right side, which was not covered by the shield each soldier carried with his left arm' (Hammond).
sin…vellent: contrasted with cum reverti coeperant. The subjunctive is occasionally used to denote repeated action in a subordinate clause, instead of the more usual imperfect or pluperfect indicative (Hodges); vellent: not contrary to fact, but a future condition thrown into the past. ( A&G 516.f)
ad horam octavam: i.e., until between 2 and 3 p.m. The Romans divided the period of daylight into 12 hours, which varied in length depending on the time of year (Gaisser) ( A&G 424.e).
T. Balventio: dative of disadvantage. (You’ll soon see why.) (Gaisser) ( A&G 376).
primum pilum duxerat: ‘Had been chief centurion’. (Anthon)
in adversum os: 'right in the face' (Gaisser).
funda: '(a missile sent by) a sling'; ablative of means (Gaisser) ( A&G 409).