26 Depth of the Ocean. 



board the " Voringen." The latter obtained a sounding of 1800 

 fathoms about half-way between Iceland and Norway. As a 

 general result of the soundings taken in this basin, it appears that 

 an area of depression of over 1000 fathoms in depth extends 

 southward from the strait between Spitzbergen and Greenland, 

 in lat 8o° N., as far as the Faeroe Islands, and occupies the 

 central part of the space between Greenland, Iceland, and Nor- 

 way, gradually shelving up towards their shores. The volcanic 

 island of Jan Mayen rises from the bottom of this area to a 

 height of 6870 feet above the sea-level. The only deep-sea 

 communication between this basin and the Atlantic seems to be 

 effected by Denmark Strait, the unexplored space between 

 Iceland and Greenland. According to the temperature-sound- 

 ings of the " Voringen," a mass of cold water under o° C. 

 fills up this basin to within 400 fathoms of the sea-surface on 

 the Norwegian side, and to within 200 fathoms towards the 

 east coast of Iceland. An extension of this cold stratum was 

 discovered by H.M.S. " Lightning" and "Porcupine" in the 

 500- fathom channel between the Faeroe Islands and the British 

 plateau. 



