How many troops Hasdrubal carried over to Italy, is not exactly known to us, as we are left here without Polybius.[28] He did not march with a large army from Spain; but, with the skill of his father and brother, he increased it in Gaul. Many a messenger, as Livy expressly tells us, had in those days stolen across the Alps over to Hannibal in Apulia; so that the Alpine tribes had already become acquainted with the Carthaginians. Moreover, by a twelve years’ intercourse the people there were convinced, that the passage through their country was only a secondary object, and that therefore it was their interest to grant it under fair conditions. Hasdrubal avoided the blunder made by his brother in starting too late; in the autumn his preparations were ended, and he now set out, going a great way round. It is evident, on a careful collation of the different statements, that after a short engagement with Scipio, he marched from the country of the Celtiberians, not through Catalonia, but through Biscay, by what is now Bayonne, along the north side of the Pyrenees; so as to elude the Romans, and not be stopped by them. In the south of Gaul, he took up his winter-quarters somewhere in modern Roussillon, and was able to start from thence by the first beginning of spring. We learn from Livy, that at that time the Arvernians had the _principatus Galliæ_, and that they allowed him a free passage. He now reached Italy without any mischance, because he had started early enough. When it is said that he had gone over the ground which had taken Hannibal five months, in two, this applies only to his march from the Pyrenees to Placentia, whereas Hannibal had set out from New Carthage.