In the earlier ages of the human race, when their numbers were yet few, and the whole world was before them where to choose the most eligible places for habitation, we may have no difficulty in imagining that many families might wander away so widely from their fellow men as to become completely isolated, growing up eventually into nations with languages, institutions, and social habits peculiar to themselves. As they so grew up into nations, the whole course of history shows us that they would become divided into minor sections, into opposite parties and contending factions, bearing upon one another in their own community and pressed upon by other branches of their family, or by other families which had also grown up into nations in like manner in adjacent countries. So long as the world afforded ample room enough for them to have places of refuge where to retire from more powerful parties, it was no great hardship for any weaker tribe to wander on, if thus pushed forward to the furthest confines of the habitable world. But in the course of such events, all the more eligible situations on the several continents would in no great length of time become occupied and eventually objects of contention, so that as the tide of population pressed on, the weaker parties would be compelled to retire to what would be otherwise ineligible situations, occupied only as the most inaccessible to their enemies.
At the time of Caesar's conquest of Gaul, we learn that Britain had already become densely populated: "Hominum est infinita multitudo, creberrimaque ædificia;" and this must have been occasioned by the pressure of advancing population. At the same time the tribes on the main land who had not been able to cross the seas in search of securer abodes, were obliged to seek protection in such fastnesses as they could find, whether of mountainous districts or others. One tribe in that age amongst the Batavi thus seems to have already settled on the dubious lands since designated as the Low Countries, and given them the character they have ever since held as rescued from the ocean. It must have been the direst necessity alone that could have driven them into such abodes, and into adopting such means as even so early in their history the inhabitants had recourse to in their perilous situation for banking out the sea, and constructing their habitations beneath its approaches. Pliny, who wrote so shortly after Cæsar, describes their country in almost the same terms as we might employ in the present day, as a land where the ocean pours in its flood twice a day, and produces a perpetual uncertainty whether it should be considered
