In C. H. Pearson's "Historical Maps of England During the first Thirteen Centuries" there is abundant evidence of the way in which towns and trading centres in Britain grew up {109}along the course of navigable rivers, while the country at any distance therefrom remained unoccupied, however important the places that may be found there to-day. On the map of Saxon England, for instance, mention is made of Gleaweceaster (Gloucester; spelling from "Saxon Chronicle"), Teodekesberie (Tewkesbury; "Domesday"), Brycgnorth (Bridgnorth; "Saxon Chronicle"), and Scrobbesbyrig (Shrewsbury; "Saxon Chronicle"), but no one can doubt that these places attained to their early importance mainly because of their situation on the river Severn. Other typical inland cities or towns include London and Oxford on the Thames; Ware on the Lea; Rochester on the Medway; Peterborough on the Nen; Lincoln on the Witham; York on the Ouse; Doncaster on the Don; Cambridge on the Cam; Norwich on the Yare; Colchester on the Colne; Ludlow on the Terne; Exeter on the Exe; Winchester on the Ouse (Sussex); Hereford on the Wye; Chester on the Dee; Caerleon (Isca) on the Usk; and so on with many other places, the location of which alongside a river must doubtless have been due, in part, it may be, to the convenience of water supply, and in part, also, to the greater fertility of the river valley, but more especially to the facility offered by the water highway for transport when other highways were either lacking or far less convenient. Adam Smith, in his "Wealth of Nations" (Book I., chapter xi., pages 20-1), compares the cost of sending goods by road from London to Edinburgh with that of forwarding them by sea, and adds:-- "Since such are the advantages of water carriage it is natural that the first improvements of art and industry should be made where that conveniency opens the whole world for a market to the produce of every sort of labour, and that they should always be much later in extending themselves into the inland parts of the country. The inland parts of the country can for a long time have no other market for the greater part of their goods but the country which lies round about them, and separates them from the sea coast and the great navigable rivers. The extent of their market, therefore, must for a long time be in proportion to the riches and populousness of that country, and consequently their improvement must always be posterior to the improvement of that country. In our {110}North American colonies the plantations have constantly followed either the sea coast or the banks of the navigable rivers, and have scarce anywhere extended themselves to any considerable distance from both." On the Continent of Europe the location of the chief inland centres of trade, commerce, and industry was no less decided by the convenience of transport afforded by the great navigable rivers, as shown (to give two examples only) by Augsburg on the Danube and Cologne on the Rhine.