316 Mr G. A. Rowell on the 



i, e. about 72" of north latitude. Passing westward it de- 

 scends to the 54th degree of latitude, and shews a mean tem- 

 perature of 20° lower in the eastern parts of America, when 

 compared with the same latitudes in Iceland, England, and 

 the north-western parts of Europe. 



This difference of temperature is generally attributed to 

 the effects of the Gulf Stream ; but although there is high 

 authority for this opinion, I venture to suggest that other 

 causes operate in a much greater degree in producing this 

 phenomenon. That the temperature of the Atlantic Ocean 

 has some effect I do not deny, but the proofs of a continua- 

 tion of the Gulf Stream, or of there being any stream from 

 the Atlantic into the Arctic Sea, are very meagre, chiefly, I 

 believe, depending on the fact, that plants from the Gulf of 

 Mexico and the West Indian Islands are occasionally found 

 on the shores of England, Iceland, Norway, &c. ; but when 

 we consider the vast quantity of such materials brought by 

 the Gulf Stream into the midst of the Atlantic, it is reason- 

 able to suppose that the whole of its shores must occasionally 

 have some of these things thrown on them by storms, &c. 

 I am not aware that the Gulf Stream can be traced farther 

 north than the 49th degree of latitude, and the fact that a 

 bottle thrown into the sea by Sir W. E. Parry, in latitude 

 53° 13' north, longitude 46° 55' west, was picked up on the 

 shore of Tenerifle, seems to support this idea, as it must 

 have crossed the direction of this supposed stream. 



It is a very general opinion that the western sides of con- 

 tinents are always warmer than the eastern ; but this is not 

 supported by facts, as the temperature of Africa is lowest 

 on the western side, and the same is the case with the whole 

 of America, from the 30th degree of north latitude to Cape 

 Horn. 



I beg to suggest, that the principal cause of the unequal 

 distribution of temperature in high northern latitudes is the 

 blocking up of the ice in the seas above the Asiatic and 

 American continents, thus making those parts the poles of 

 cold, whilst the Arctic Sea being open from Norway to 

 Greenland no such accumulation of ice can take place there, 

 consequently the temperature is higher there than in any 



