PORT ECONOMICS 
on the banks of rivers, by which access may be obtained 
to the seas and the great ocean highways. Basle, for 
instance, on the borders of Switzerland and over 450 miles 
from the sea, is a port for barges and light river craft, 
and it even aspires to the rank of a seaport, in that it 
desires to receive vessels capable of navigating open water. 
The advantage, indeed, of an actual seaboard, to a country 
in regard to its foreign trade, is incalculable. More than 
one war, in recent times, has been caused by the en- 
deavours of a landlocked nationality to find an outlet to 
the coast. 
But a position on the coast-line is not an unmixed blessing 
to a port, as we have already seen. The exposure to violent 
storms entailed by such a location necessitates a heavy 
expenditure on protective works, all of which has to be 
defrayed out of trading profits, either directly, through 
the charges of the port authority, or indirectly, to the 
State in the form of taxation. 
As indicated above, many ports are situated on the 
banks of rivers at varying distances inland. Some are at 
the mouths of rivers, such as Liverpool, Dublin, Bremen, 
and hence may be distinguished as Estuary Ports.? Other 
ports are situated some distance from the river mouth. 
London is about 50 miles from the sea; so is Antwerp ; 
Rouen is a thriving French port on the Seine about 80 miles 
from the English Channel ; Cologne, a German port on the 
Rhine, is some 200 miles from the North Sea; and Basle, 
mentioned above, also on the Rhine, is over 450 miles 
from the sea. Naturally, when the distance from the sea 
is considerable, the navigable channel does not admit 
of the passage of the larger class of vessels characteristic 
1 The term Estuary is a little vague, but without being 
pedantically precise, it covers roughly the extent of the river which 
is appreciably affected by the tide—that is, the portion in which 
there is tidal flow, in and out. This admittedly cannot strictly 
apply to rivers flowing into a * tideless ” sea, such as the Medi- 
terranean, but it suffices to explain the idea in a general way. 
It is the region of ‘ turbulence” (Lat. @stuare, to seethe, or 
boil), in which there is conflict between effluent and influent waters. 
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