Disadvantages of River Navigation 157 



natural condition, even in the lower portions of their course ; 

 and, owing to the continual changes taking place in their 

 channels and at their outlets, they are liable to deteriorate 

 if left to themselves." Left to themselves the English rivers, 

 like the Roman and the British roads, were for a thousand 

 years after the departure of the Romans, and the liability 

 to deteriorate may well have shown itself during this period, 

 before even the earliest of the River Improvement Acts was 

 passed ; though the deterioration due to the ceaseless opera- 

 tions of Nature may obviously continue in spite of all Acts of 

 Parliament, and notwithstanding a great expenditure of money. 



The fate that has overtaken so many English rivers which 

 once counted as highways of commerce may be compared 

 with the fate that, also through the operation mainly of 

 natural causes, has overtaken many of our once flourishing 

 sea ports. 



When, in the thirteenth century, Liverpool was raised to 

 the rank of a free borough, there were between thirty and 

 forty places which, whether situated on the coast or some 

 distance inland (as in the case of York), were counted as sea- 

 ports. Their order of importance at that time is shown by 

 the following table (taken from Baines's " History of Liver- 

 pool "), which gives the taxation then levied on each ; though 

 the amounts stated should be multiplied by fifteen to ascer- 

 tain their equivalent in the money of to-day : 



