But it would seem that Airy was not quite convinced of the soundness of his own reasoning. ‘If,’ he says, ‘any reader thinks that the reasons for excluding the Portus Itius from the land of the Morini are not sufficiently cogent, the whole is easily reconciled with the hypothesis that the Portus Itius was the mouth of the Somme by supposing that in the time of Caesar the Morini stretched south-west of the Somme ... the geography which limits their territory to the north of the Somme is 120 years later. Any one who reflects on the change of boundary of Russia, of Prussia, of Turkey, and of other European States, within a period of much less than 120 years, will find no difficulty in admitting this change in the limits of the Morini.’[2736]
It is sufficient to answer that there is no analogy between the political history of Europe in the earlier half of the nineteenth century and that of Gaul in the 120 years that followed the invasion of Britain by Caesar. The Gallic peoples during that period were not at war with one another; and there is not the slightest reason to suppose that the Morini possessed a wider seaboard in Caesar’s time than 120 years later. Lewin’s reply to Airy is worth quoting[2737]:—‘He offers, as a solution of the difficulty, that in the time of Caesar the Morini stretched south-west of the Somme. If so, then the Somme itself, from which Caesar sailed, and to which he returned, was, according to the Astronomer-Royal, in the country of the Morini; and yet, a few lines before, the Astronomer-Royal had stated that the order (after Caesar’s second return) for legions to march into the country of the Morini made it certain that he was not in their country! Thus to avoid Scylla, it is laid down, as certain that Caesar did not sail from the Morini; and then, to avoid Charybdis, the reader is invited to assume that the place of embarkation was amongst the Morini.’
Finally, Airy affirms that the mouth of the Somme was by far the best harbour which Caesar could have selected, and that its capability for his purpose ‘is proved by the ... experience of William of Normandy, who at one tide floated out of it 1400 ships’.[2738]
Now William the Conqueror assembled his fleet and embarked his army not in the mouth of the Somme but in the mouth of the Dive:[2739] he was merely obliged, as Lewin says,[2740] ‘to take temporary shelter ... at the mouth of the Somme.’ But this blunder is of no great consequence. The Somme might have served Caesar’s purpose if only it had not been twice as far from that part of Britain to which he intended to go as Boulogne.
VI. AMBLETEUSE
The Commission de la Topographie des Gaules[2741] identify the Portus Itius with Ambleteuse; and Mommsen[2742] is disposed to agree with them. They argue that Strabo[2743] affirms the existence of two ports in the country of the Morini; that one of the two was evidently Gesoriacum; and that the Portus Itius was therefore something different. The passage in Strabo to which the commission refers will be most conveniently examined in a later section.[2744] Meanwhile it is enough to say that if it proves that the Portus Itius was not Gesoriacum, it does not prove that the Portus Itius was Ambleteuse.
General Creuly[2745] decides for Ambleteuse on the ground that its distance from Wissant corresponds with Caesar’s statement of the distance which separated his own port of embarkation from the ulterior portus, and that the intervention of Cape Grisnez between Ambleteuse and Wissant would have justified Caesar in describing the latter as the ulterior portus. He remarks that if the Portus Itius is identified with Boulogne, the ulterior portus must have been Ambleteuse. But, referring to Vergil’s well-known line—tendebantque manus ripae ulterioris amore[2746]—he argues that the word ulterior implies the intervention between the Portus Itius and the ulterior portus of an ‘objet disjonctif’, such as a promontory; and he insists that no such ‘objet’ intervenes between Boulogne and Ambleteuse. But Heller[2747] observes that a passage in the Germania[2748] of Tacitus—(Gerunt et ferarum pelles), proximi ripae negligenter, ulteriores exquisitius—would seem to show that ulterior means much the same as longinquior.[2749] Besides, if the distance from Ambleteuse to Wissant justifies us in identifying Ambleteuse with the Portus Itius and Wissant with the ulterior portus, the distance from Boulogne to Ambleteuse, as I shall presently show, equally justifies us in identifying Boulogne with the Portus Itius and Ambleteuse with the ulterior portus.[2750]
Not a single valid argument ever has been or can be adduced in favour of Ambleteuse. The harbour is far too small to have contained Caesar’s fleet; and the merest tiro in his army could have decided at a glance between its merits and those of Boulogne.[2751]
VII. CALAIS
I only consider the claims of Calais because their one modern advocate, General von Göler,[2752] was a distinguished Caesarian scholar. There is no evidence that Calais was ever used as a harbour in, or for twelve centuries after, the time of Caesar. If Caesar started from the Portus Itius on his first expedition, it is impossible, on the theory that Calais was the Portus Itius, to find the ulterior portus. Moreover, it would have been impossible for Caesar to sail, on his second expedition, from Calais to any point of the Kentish coast between Walmer and Sandwich.[2753] For, as the wind was from the south-west, he would have had to sail within seven points and a half of the wind on a flood tide, which would have tended to carry him into the North Sea, and with shallow flat-bottomed vessels which made excessive lee-way.[2754] Finally, Calais Harbour is not natural but artificial; and it is certain that it did not exist in the time of Caesar.[2755]