It is interesting, in connection with this economic aspect of the Thames Valley, to note that, alone of the great river valleys of Europe, it has no railway system parallel to its banks. There is no series of productive centres which could give rise to such a railway system. The Great Western Railway follows the river now some distance upon one side, now some distance upon the other, as far as Oxford; but it does not depend in any way upon the stream, and where the course of the stream is irregular it goes on its straight course, throwing out branch lines to the smaller towns upon the banks: for the railway depends, so far as this section is concerned, upon the industries of the Midlands and of the west. Were you to cut off the sources of carriage which it draws upon from beyond the Valley of the Thames it could not exist. The Scheldt, the Rhine, the Rhone, the Garonne, the Seine, the Elbe, are all different in this from the Thames. The economic power of our main river valley is chiefly a spending power. It produces little and, though it exchanges more of human wealth, it is the artificial machinery of exchange rather than the physical movement of goods that enriches it. Now this habit of residence, this settlement of the concentrated power of demand upon the banks of the Thames, was the work of the monastic houses. It may be argued that, with the commercial importance of London, and with its attainment of the position of a capital, the residence of such economic power would necessarily have spread up the Thames Valley. It is doubtful whether any such necessity as this existed. In Roman times the Thames certainly did not lead up thus in the line of wealth from London, and though it is true that water carriage greatly increased in importance after the breakdown of Roman civilisation, yet the medium by which that water carriage was utilised was the medium of the Benedictine foundations. They it was who established that continuous line of progressive agricultural development and who prepared the way for the later yet more continuous line of the full monastic effort which succeeded the Conquest.