CUNTOUR AND GENERAL APPEARANCE. 153 
In 1867, in a journey made along these coasts, Professor 
Daa traversed the interior from Kola to the White Sea 
and the Gulf of Bothnia, and had an opportunity of obser- 
ving the causes of these apparently conflicting phenomena. 
These are sufficiently simple. The formation of ice on the 
surface of the ocean depends on the concurrence of many 
causes, amongst which the cold is one of but relative 
importance. Ice is formed more easily in inland basins, 
where the water is not so deep, is more mixed with fresh 
water, and is less exposed to great ocean waves. It is 
thus that the ice is formed in the Baltic, on the Zuyderzee, 
and sometimes even in the Adriatic. It is then natural 
that the interior parts of Norwegian fiords should also 
freeze. The port of Christiana, for example, is for some 
months closed by thick ice, which it is necessary to saw or 
break up by means of powerful steam vessels. On the 
contrary, on the margin of the ocean, the unceasing move- 
ment of the waves hinders congelation. Again, the interior 
waters offer the best protection for ships, and it is near to 
them that are found the most convenient positions for 
towns, and for communication with productive inland 
lands. The Russians, a people more especially agricul- 
tural, have built all their towns in interior localities, in 
order that communication may be had by rivers with their 
richest and most productive provinces. Now in inland 
seas the ice is formed for many miles on end, and naviga- 
tion becomes impossible during winter. The Norwegians, 
who find their principal resources in navigation and fishing, 
have preferred building their towns on the shores of the 
ocean, The inconveniences thence resulting are many, 
and the ports are only of middling character. The Nor- 
wegian Assembly has been obliged to vote a sum of about 
two millions of francs to improve the port of Vardoe. But 
on the other hand, by nature or by art, it has been brought 
about that navigation can be carried on there continuously 
without interruption. It would, however, be erroneous to 
suppose that Norway constitutes an exception to the known 
laws of temperature, or that no natural obstacles to navi- 
gation exist there. 
