204 THE GULF STllEAM. 



a south-easterly wind drives it nearer the coast, and a north-westerly 

 wind drives it further out into the ocean. Near the Bahama coast the 

 breadth is fifteen leagues, in latitude 28° 30' it is seventeen leagues, and 

 under the parallel of South Carolina from forty to fifty leagues. Ves- 

 sels may shorten their passage from North America to Europe by keep- 

 ing in this stream, and in returning by avoiding it. 



Tlie rise of the mercury in the thermometer always indicates the 

 presence of the Gulf stream. It is also known by the appearance and ele- 

 vated temperature of thewater, and, in fair weather, by its smooth and 

 clear surface, as well as its indigo-bhie color. The margin of the stream 

 is marked bv a ripple on its edge ; in some places the water appears to 

 boil and in others to foam like the waters of a cataract, even in a dead 

 calm and in I'alhomless spots. It is further recognized by the gulf-weed 

 wliich is every where interspersed, and by tlie heat of the adjacent at- 

 mosphere which in the winter season is very perceptible. In high lati- 

 tudes it is always covered with a thick fog. 



What is the most rational hypothesis as to its origin ?■ How is it oc- 

 casioned? Several explanations have been given. It has been ascribed 

 by some to the influence of the water flowing from the Mississippi. 

 This to us seems unsatisfactory, for although the river may contribute 

 in some small degree to the formation of the stream, our objection is 

 founded on the inquiry, How is the greater warmth of the water than 

 the surrounding ocean water accounted for ? In adtiition, its extent is 

 greater than the Mississippi, being in some places fifty miles. 



2ndly. Tlie revolution of the eartli has been offered by some as an 

 adequate explanation of the phenomenon. If this view be correct, why, 

 we ask, is its influence not general in its operation. We find that evea 

 in the same stream there is a variation. 3dly. Others attempt a solution 

 of the difUculty by referring its origin to a subterraneous passage at the 

 isthmus of Darien, and its heat to the presence of volcanos. This has 

 the least claim to our favor, because the water on the Atlantic side is al- 

 ways the higher, being fourteen feet higher than on that of the Pacific 

 side. 



That which we are disposed to regard as the most plausible explan- 

 ation is its reference to the easterly trade winds, the impulse given by 

 them to the surface of the water, driving it into the Gulf of Mexico, 

 where, getting above its natural level, it endeavors to seek it by running 

 between the Bahamas and the Florida shore ; it then takes a direction 

 along the coast of America over the southern extreme of the Bank of 

 Newfoundland, thence through and among the Western Islands, then it 

 takes a south-easterly direction, spreads out to a greater breadth among 



