England has been built up upon the framework of her rivers, and, in that pattern, the principal line has been the line of the Thames. Partly because it was the main highway of Southern England, partly because it looked eastward towards the Continent from which the national life has been drawn, partly because it was better served by the tide than any other channel, but mainly because it was the chief among a great number of closely connected river basins, the Thames Valley has in the past support