on the right bank here the rocks and precipices come so close to the river that there remained only a narrow path which could easily be blocked up, and the Sequani, to whom this bank belonged, could with ease intercept the route of the Helvetii.  They preferred therefore to pass over, above the point where the Rhone breaks through, to the left Allobrogian bank, with the view of regaining the right bank further down the stream where the Rhone enters the plain, and then marching on towards the level west of Gaul; there the fertile canton of the Santones (Saintonge, the valley of the Charente) on the Atlantic Ocean was selected by the wanderers for their new abode.  This march led, where it touched the left bank of the Rhone, through Roman territory; and Caesar, otherwise not disposed to acquiesce in the establishment of the Helvetii in western Gaul, was firmly resolved not to permit their passage.  But of his four legions three were stationed far off at Aquileia; although he called out in haste the militia of the Transalpine province, it seemed scarcely possible with so small a force to hinder the innumerable Celtic host from crossing the Rhone, between its exit from the Leman lake at Geneva and the point of its breaking through the mountains, over a distance of more than fourteen miles.  Caesar, however, by negotiations with the Helvetii, who would gladly have effected by peaceable means the crossing of the river and the march through the Allobrogian territory, gained a respite of fifteen days, which was employed in breaking down the bridge over the Rhone at Genava, and barring the southern bank of the Rhone against the enemy by an entrenchment nearly nineteen miles long:  it was the first application of the system—­afterwards carried out on so immense a scale by the Romans—­of guarding the frontier of the empire in a military point of view by a chain of forts placed in connection with each other by ramparts and ditches.  The attempts of the Helvetii to gain the other bank at different places in boats or by means of fords were successfully frustrated by the Romans in these lines, and the Helvetii were compelled to desist from the passage of the Rhone.

The Helvetii Move towards Gaul

On the other hand, the party in Gaul hostile to the Romans, which hoped to obtain a powerful reinforcement in the Helvetii, more especially the Haeduan Dumnorix brother of Divitiacus, and at the head of the national party in his canton as the latter wasat the head of the Romans, procured for them a passage through the passes of the Jura and the territory of the Sequani.  The Romans had no legal title to forbid this; but other and higher interestswereat stake for them in the Helvetic expedition than the question of the formal integrity of the Roman territory—­ interests which could only be guarded, if Caesar, instead of confining himself, as all the governors of the senate and even Marius(34) had done, to the modest task of watching the frontier, should cross what had hitherto been the frontier at the head of a considerable army.  Caesar was general not of the senate, but of the state; he showed no hesitation.  He had immediately proceeded from Genava in person to Italy, and with characteristic speed brought up the three legions cantoned there as well as two newly-formed legions of recruits.