Seeing that for the time, at any rate, all was lost in Spain, Hasdrubal set out with an army to join his brother Hannibal. In Auvergne, in the centre of Gaul, where he spent the winter, large numbers of Gallic tribes joined him, and in the spring he crossed the Alps by the same pass as Hannibal. But the difficulties of nine years earlier were now absent, for the mountaineers understood at last that no evil to them was intended, and let the Carthaginian army climb the defile without attempting to hurt them. Traces of Hannibal's roads remained everywhere, and thus the troops, consisting perhaps of sixty thousand men, marched easily along and descended into the plains of the Po. But it was all useless; before Hasdrubal could join Hannibal, who was still in Apulia, the consul Nero, encamped near by at the head of a considerable force, made prisoners some messengers sent by the general to his brother. Instantly taking steps to have the roads to the north watched by armies, Nero set off at night with a picked detachment to meet the consul Livius on the coast of the Adriatic, south of the river Metaurus. Night and day his men marched, eating as they went food brought them by the peasants. In less than ten days they had gone two hundred miles, and entered the camp of Livius by night, so that the Carthaginian general might know nothing of their arrival. Next morning Nero insisted, against the opinion of the other generals, that battle should be given immediately, as he must return and meet Hannibal at once. In vain they protested that his troops were too tired to fight; he shut his ears, the signal was sounded, and the army drawn up. * * * * * The Carthaginians had already taken their places at the time that the Romans began to form, when Hasdrubal, riding down his lines to make sure that everything was done according to his orders, noticed that among the enemy's array clad in shining armour were a band with rusty shields, and a bevy of horses which looked lean and ill-groomed. Glancing from the horses to their riders, he saw that their skins were brown with the sun of the south and their faces weary. No more was needed to tell him that reinforcements had come, and that it would be madness to risk a fight. He could do nothing during the day, but as soon as the night came he silently broke up his camp and started for the river Metaurus, hoping to put it between him and the Romans; but it was too late. Had the Carthaginian army only consisted of old and well-seasoned troops all might have gone well with it; but the large body of Gauls were totally untrained, and in their disappointment at not being allowed to give battle, seized on all the drink in the camp, and fell along the roadside quite unable to move. Before Hasdrubal could get his vanguard across the Romans were close upon him, and there was nothing left for him to do but to post his men as strongly as he could.