V. This agitation having been calmed, Cæsar sought information concerning the roads from Divitiacus, who, of all the Gauls, inspired him with the greatest amount of confidence. In order to proceed from Besançon to the valley of the Rhine, to meet Ariovistus, the Roman army had to cross the northern part of the Jura chain. This country is composed of two very distinct parts. The first comprises the valley of the Doubs from Besançon to Montbéliard, the valley of the Oignon, and the intermediate country, a mountainous district, broken, much covered with wood, and, without doubt, at the time of Cæsar’s war in Gaul, more difficult than at present. The other part, which begins at the bold elbow made by the Doubs near Montbéliard, is composed of lengthened undulations, which diminish gradually, until they are lost in the plains of the Rhine. It is much less wooded than the first, and offers easier communications. (_See Plate 4._) Cæsar, as he had announced, started early on the morrow of the day on which he had thus addressed his officers, and, determined on conducting his army through an open country, he turned the mountainous and difficult region just described, thus making a circuit of more than fifty miles (seventy-five kilomètres),[218] which is represented by a semi-circumference, the diameter of which would be the line drawn from Besançon to Arcey. It follows the present road from Besançon to Vesoul as far as Pennesières, and continues by Vallerois-le-Bois and Villersexel to Arcey. He could perform this distance in four days; then he resumed, on leaving Arcey, the direct road from Besançon to the Rhine by Belfort and Cernay. On the seventh day of a march uninterrupted since leaving Besançon, he learnt by his scouts that the troops of Ariovistus were at a distance of not more than twenty-four miles (36 kilomètres). Supposing 20 kilomètres for the day’s march, the Roman army would have travelled over 140 kilomètres in seven days, and would have arrived on the Thur, near Cernay. (By the road indicated, the distance from Besançon to the Thur is about 140 kilomètres.) At this moment, Ariovistus would have been encamped at 36 kilomètres from the Romans, to the north, near Colmar. Informed of the arrival of Cæsar, Ariovistus sent him word “that he consented to an interview, now that the Roman general had come near, and that there was no longer any danger for him in going to him.” Cæsar did not reject this overture, supposing that Ariovistus had returned to more reasonable sentiments.