THE GULF STREAM. 23 



ceaseless in their operations as the siin in his course, and in their 

 effects they are as endless. Philosophy points to them as the chief 

 cause of the Griilf Stream and of all the constant currents of the sea. 



74. Early writers, however, maintained that the Mississippi 

 Early writers. Eivcr was the father of the Grulf Stream. . Its floods, 



they said, produce it : for the velocity of this river in the sea (§70) 

 might, it was held, be computed by the rate of the cmxent of the 

 river on the land. 



75. Captain Livingston overturned this h3-pothesis by showing 

 Objection to the that tho volume of water vrhich the Mississippi 

 fresh-water theory, j^^^.g^, empties iuto the Gulf of Mcxico is not equal 

 to the three thousandth part of that which escapes from it through 

 the Grulf Stream. Moreover, ih.Q water of the Gulf Stream is salt 

 — that of the Mississippi, fresh ; and the advocates of this fresh- 

 water theory (§ 74) forgot that just as much salt as escapes from 

 the Gulf of Mexico through this stream, must enter the Gulf 

 through some other channel from the main ocean ; for, if it did not, 

 the Gulf of Mexico, in process of time, unless it had a salt bed at the 

 bottom, or was fed with salt springs from below — neither of which 

 is probable — would become a fresh- water basin. 



76. The above-quoted argument of Captam Livingston, however, 

 Livingstons hypo- was held to be conclusive; and upon the remains 

 *^^^^^- of the hypothesis which he had so completely over- 

 turned, he set up another, Avhich, in turn, has also been upset. In 

 it he ascribed the velocity of the Gulf Stream as depending " on the 

 motion of the sun in the ecliptic, and the influence he has on the 

 waters of the Atlantic." 



77. But the opinion that came to be most generally received and 

 Franklin's theory, dcep-rooted in the miud of seafaring people w^as the 



one repeated by Dr. Franldin, and which held that the Gulf Stream 

 is the escaping of the waters that have been /orcefZ into the Carib- 

 bean Sea by the trade-winds, and that it is the pressure of those 

 winds upon the water which drives up into that sea head, as it were, 

 for this stream. 



78. We know of instances in which the waters have been accu- 

 objections to it. mulatcd on one side of a lake, or in one end of a 



canal, at the expense of the other. The pressm-e of the trade- 

 winds may assist to give the Gulf Stream its initial velocity, but are 

 they of themselves sufficient to send such a stream of water all the 

 way across the ocean, projecting by a single impress a volume of 

 water from the phores of America to the shores of Europe, that 



