De Bello Gallico 1.8

1.8.1Intereā eā legiōne quam sēcum habēbat mīlitibusque, quī ex prōvinciā convēnerant, ā lacū Lemannō, quī in flūmen Rhodanum īnfluit, ad montem Iūram, quī fīnēs Sēquanōrum ab Helvētiīs dīvidit, mīlia passuum XVIIII mūrum in altitūdinem pedum sēdecim fossamque perdūcit.

Meanwhile, with the legion he had with him and the soldiers who had gathered from the Province, he builds a wall nineteen miles long and sixteen feet high, with a trench, from Lake Geneva, which flows into the river Rhône, to the Jura range, which divides the territory of the Sequani from the Helvetii.

Note. mīlia passuum XVIIII: 'for nineteen miles', accusative of extent. in altitūdinem pedum sēdecim: 'sixteen feet high'.

1.8.2Eō opere perfectō praesidia dispōnit, castella commūnit, quō facilius, sī sē invītō trānsīre cōnentur, prohibēre possit.

When this work was finished he posts garrisons and fortifies redoubts, so that he could more easily stop them if they tried to cross against his will.

Note. quō facilius: quō introduces a purpose clause containing a comparative. sē invītō is an ablative absolute: 'against his will'.

1.8.3Ubi ea diēs quam cōnstituerat cum lēgātīs vēnit et lēgātī ad eum revertērunt, negat sē mōre et exemplō populī Rōmānī posse iter ūllī per prōvinciam dare et, sī vim facere cōnentur, prohibitūrum ostendit.

When the day he had set with the envoys came and the envoys returned to him, he says that by the custom and precedent of the Roman people he cannot give anyone passage through the Province, and he makes clear that he will stop them if they try to use force.

1.8.4Helvētiī eā spē dēiectī nāvibus iūnctīs ratibusque complūribus factīs, aliī vadīs Rhodanī, quā minima altitūdō flūminis erat, nōn numquam interdiū, saepius noctū sī perrumpere possent cōnātī, operis mūnītiōne et mīlitum concursū et tēlīs repulsī, hōc cōnātū dēstitērunt.

The Helvetii, thrown from this hope, tried to break through, some by boats joined together and many rafts they had made, others by the fords of the Rhône where the river was shallowest, sometimes by day, more often by night; driven back by the fortifications, the rush of soldiers and their weapons, they gave up the attempt.

Note. sī perrumpere possent: 'to see whether they could break through'; sī can mean 'whether' after verbs of trying.