to their colonial settlements in the south of Gaul. Of these the city of Narbonne, situated about as far to the west of the mouth of the Rhone as the Greek city of Marseilles stood to the east of it, was the chief, as well as one of the oldest, having been founded about the year B.C. 120, The historian Diodorus Siculus, who was contemporary with Julius Cæsar, has given us an account of the manner in which the trade between Britain and Gaul was carried on in his day, which, although it does not expressly mention the participation of either the Romans or any of their colonies, at least shows that the Cassiterides and the island of Britain had become better known than they were a hundred years before in the time of the younger Scipio. Diodorus mentions the expedition of Caesar, of which he promises a detailed account in a part of his history now unfortunately lost; but he tells us a good many things respecting the island, the knowledge of which could not have been obtained through that expedition. We must, therefore, suppose that he derived his information either through an intercourse with the country which had arisen subsequent to and in consequence of Cæsar's attempt, or, as is much more probable, from the accounts of those by whom the south-western coast had been visited long before. . Indeed, various facts concur to show that, however ignorant of Britain Cæsar himself may have been when he first meditated his invasion, a good deal was even then known about it by those of the Greeks and Romans who were curious in such inquiries. Caesar notices the fact of tin, or white lead, as he calls it, being found in the country; but he erroneously places the stores of this mineral in the interior (in mediteraneis regionibus), probably from finding that they lay a great distance from the coast at which he landed; and he does not seem to have any suspicion that this was really the famous Land of Tin, the secret of whose situation had been long guarded with such jealous care by its first discoverers, and which his own countrymen had made so many anxious endeavours to find out. But a century and a half before this date Polybius, as he tells us himself, had intended to write
