Placed on almost inaccessible heights, these vast Gaulish _oppida_, which enclosed the greater part of the population of a province, could only be reduced by famine. Cæsar was well aware of this, and resolved on confining himself to the blockade of Gergovia; but one day he judges the occasion favourable, and he risks an assault. Repulsed with loss, he thinks only of retreat, when already the insurrection surrounds him on all sides. The Burgundians themselves, who owe everything to Cæsar, have followed the general impulse: by their defection, the communications of the Roman army are intercepted and its rear threatened. Nevers is burnt, and the bridges on the Loire are destroyed; the Gauls, in their presumptuous hope, already see Cæsar humiliated, and obliged to pass with his soldiers under new Furcæ Caudinæ; but old veteran troops, commanded by a great captain, do not recoil after a first reverse; and these six legions, shut up in their camp, isolated in the middle of a country in insurrection, separated from all succour by rivers and mountains, yet immovable and unshaken in face of a victorious enemy who dares not pursue his victory, resemble those rocks beaten by the waves of the ocean, which defy the tempests, and the approach to which is so perilous that no one dare brave them. In this extremity Cæsar has not lost hope. Far from him the thought of re-crossing the Cévennes, and returning into the Narbonnese. This retreat would bear too great a resemblance to a flight. Moreover, he has fears for the four legions entrusted to Labienus, of whom he has received no news since they went to combat the Parisii; he is anxious to rejoin them at all risks. He therefore marches in the direction of Sens, crosses the Loire by a ford, near Bourbon-Lancy, and, on his arrival near Joigny, he rallies Labienus, who, after having defeated the army of Camulogenus under the walls of Paris, had returned to Sens and hastened to meet him. What joy Cæsar must have experienced, when he found his lieutenant, then faithful still, on the banks of the Yonne! for this junction doubled his forces, and restored the chances of the struggle in his favour. While he was re-modelling his army, calling to him a re-enforcement of German cavalry, and preparing to approach nearer to the Roman province, Vercingetorix had not lost a moment in stirring up the whole of Gaul against the Romans. The inhabitants of Savoy, as well as those of the Vivarais, are drawn into revolt; all is agitation from the coasts of the ocean to the Rhone. He communicates to all hearts the sacred fire which inflames him, and from Mont Beuvray, as its centre, its action radiates to the extremities of Gaul.