The Thames
that is — enjoy this peculiar advantage; and there are few things more instructive when one is engaged upon the history of England than to take a map and mark upon it the head of each navigable piece of water and the head of its tideway, for when this has been done all England, with the exception of the Welsh Hills and the Pennines, seems to be penetrated by the influence of the sea.
The conditions which give a river this great historic importance, the fundamental character, therefore, which has lent to the Thames its meaning in English history, is twofold: a river affords a permanent means of travel, and a river also forms an obstacle and a boundary. Men are known to have agglomerated in the beginning of society in two ways: as nomadic hordes and as fixed inhabitants of settlements.
There has arisen a profitless discussion as to which of these two phases came first. No evidence can possibly exist upon either side, but one may take it that with the first traditions and records, as at the present time, the two systems existed side by side, and that either was determined by geographical conditions. A river is an advantage to both groups, but to the second it is of more consequence than to the first; and in South England, if we go back to the origins of our history, it is in fixed settlements that we find the first evidence of man. With every year of research the extreme antiquity of our inhabited sites becomes more apparent. And indeed the
