THE NOETH SEA— THE BALTIC. 17 



THE KORTH SEA. 



This last section of the Xorth Atlantic, a sort of open gulf between Scandi- 

 navia and Great Britain, but communicating with other seas through the English 

 Channel and the Sound, is extremely rich in animal life. With good reason one of 

 its sections has been named Fishers' Bank, for the fish here swarm in myriads, and 

 the cod is taken alive for the markets of London and the other large cities of Xorth 

 Europe. About 900 smacks, of which 650 are owned in England, visit these banks, 

 and the yearly take is estimated at 75,000 tons. The choicest cod come from one 

 of these banks, the Dogger, or " Lugger's Bank." * The Xorth Sea, spreading its 

 shallow waters over the plateau above which rise the British Isles, ofiers these 

 excellent fishing grounds precisely because it is of no great depth, and its bed is 

 nowhere covered with rocks or stones. The only objects presenting any resistance 

 to the fishermen's trawling-nets are the oyster beds. These deep-sea molluscs 

 have little flavour ; but those of the coasts are highly esteemed, especially the 

 so-called Ostend oysters, which are brought from the shores of England to be 

 fattened in the Belgian grounds. Hundreds of millions of mussels, cockles, 

 and other shell-fish are also yearl}' taken on the sandy shores of Schleswig- 

 Holstein, and used either for making lime or enriching the land. 



AVith a greater area than the British Isles, the North Sea is limited towards 

 the Xorth Atlantic by a steep incline known as the Kinimer, and is everywhere 

 distinguished by its shallow waters, seldom exceeding 30 fathoms in depth, though 

 sinking to 103 on the east coast of Scotland. Its bed is merely a vast bank varied 

 by a number of secondary flats and shoals, and most geologists believe that during 

 the glacial period this inlet was filled by long lines of icebergs drifting with the 

 current from the glaciers of Scandinavia, Iceland, and Great Britain. f The masses 

 of ice, constantly renewed within the land-locked basin, here deposited their boulders 

 and detritus of all sorts, which gradually crumbling away, formed the bed of the 

 Xorth Sea. The process is still going on, only the débris formerly brought 

 by the icebergs is now replaced by the volcanic remains drifting with the cold 

 currents from Jan Mayen and Iceland.^ It may, indeed, be asked how the JS^orth 

 Sea has gradually been filled in, while on the south coast of Norway the Skager 

 Rak still maintains a depth of 200 to 300, and even 450 fathoms. This is pro- 

 bably due to the glaciers which formerly filled this deep trough forming an 

 extensive fiord fed by several secondary ones. Beyond this receptacle the 

 accumulated masses of ice entered the polar current, which bore them farther 

 south and distributed the débris over the bed of the Xorth Sea. 



* Xot the "Dog's Bank," as it appeared on the old maps. 



t Ramsay, " Phj-sical Geology and Geography of Great Biitain," p. 157. 



+ " Annales hydrographiques," 1873, vol. iv. 



