THE OCEAN. 



337 



latitudes is less than was once conceived. A very sensible effect in diminishing the 

 temperature of the ocean is produced by the ice annually borne by the polar currents from 

 the arctic and antarctic zones into lower latitudes. It has been met with in the South 

 Atlantic, off the Cape of Good Hope, but this is a very rare occurrence ; and did that of 

 the North Atlantic drift to a corresponding latitude, that of Cape St. Vincent, it might 

 be swept through the funnel of the Gibraltar Straits, appear in the Mediterranean, reduce 

 the temperature of that warm sea, and cloud with cold fogs the beautiful landscapes of 

 Italy. The lowest limit to which the northern ice descends appears to be 40J N. latitude. 

 Here it is occasionally encountered in a state of rapid thaw, cooling the warm water of 

 the gulf stream to a distance of forty or fifty miles around it, the thermometer gradually 

 sinking sometimes from 60 to 43 in its neighbourhood. The ice is not found, however, 

 in every part of the Atlantic under the latitude stated, but is confined to the district 

 between 42 and 56 W. longitude, which it visits in the height of summer. There is 

 only one instance on record of the ice being met with at any considerable distance on the 

 European side of this tract. This took place in the year 1817, and is sufficiently remark- 

 able to be noticed here. For nearly four centuries a large quantity of ice, having an 

 area of many thousand square miles, had occupied the sea to the north of Iceland, chiefly 

 along the eastern coast of Greenland. This icy continent, in the before-mentioned year, 

 was suddenly broken up, separated into fragments, and scattered over the waters of the 

 North Atlantic. Large masses were then found as far east as 32 of longitude, or about 

 eight hundred miles from the most westerly part of Ireland. It was conceived probable 

 that the breaking up of the great body of ice referred to had opened the navigation of the 

 sea all the way to the pole, which gave rise to the first of the expeditions of the present 



Ice Fields. 



century, to effect the north-west passage of America that under Captain Ross. This 

 dispersion of the polar ice had been ascribed at home to a diminished rigour of the 

 climate ; but upon the expedition arriving at one of the Danish factories in Baffin's Bay, 

 the resident informed the commander that during the eleven winters he had passed there 

 not one had been so severe or protracted as the last. The experience of the navigators 

 themselves speedily showed the fallacy of those sanguine anticipations which some had 

 been ready to indulge, respecting the winter of the whole northern hemisphere speedily 



