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OBSERVATIONS ON THE CUEBENTS. 



The temperature of the Caribbean Sea is above 80° F. from July to 

 October ; during the rest of the year it is below 80°, the minimum, about 

 75°, occurring in February and March. In the same latitudes, 10° to 20° N., 

 off the African coast, the lowest temperature occurs in January, and the 

 highest in July, when it rises to above 80°, as in the Caribbean Sea ; but 

 with this exception these Eastern waters are always from 3° to 7° colder 

 than the Western. It will be noticed that the maximum and the minimum 

 temperatures take place later in the year in the Caribbean Sea than off 

 the African coast. This circumstance is probably due to the prevalent 

 currents. 



The Gulf Stream keeps the sea off the Southern States, from the Missis- 

 sippi to Cape Hatter as, at a temperature above 80°, from June to October; 

 above 70° during January, February, and March ; and above 75° during 

 the intervening months, April and May, November and December. 



In striking contrast to this high and equable temperature of the seas off 

 the Southern States, is the low and variable temperature of the seaboard 

 of the Northern States, from lat, 40° to 36° N., due to the presence of the 

 cold Arctic Current. Here in January, February, and March, the tem- 

 perature of the sea falls below 50° ; in April and May, and also in 

 November and December, it is below 60°; in June and October it is 

 below 70° ; and in July, August, and September, it attains to 75°. 



Where the warm waters of the Gulf Stream intermingle with, or flow 

 side by side with, the cold Arctic Current, the changes in the temperature 

 of the sea are large and sudden, and are noticed by all navigators of that 

 region. If we contrast these extreme changes of temperature off the 

 American coast with the slow change observed off the coast of Africa, the 

 influence of Currents in modifying the temperature of the sea and deter- 

 mining climatic peculiarities becomes strikingly evident. With this view 

 the above tabular statement has been compiled from the Charts, from which 

 it appears that on the meridian of 74° W., the change of temperature from 

 lat. 40° to 35° N., or in 300 miles, is on an average 18°; while on the 



