34 THE OCEAN WORLD. 



carry the waters of the Mediterranean into the Atlantic Ocean. Its 

 existence is in some respects established by calculations which prove 

 that the quantity of salt water supplied by the upper current through 

 the Straits of Gibraltar is equal to seventy-two cubic miles per annum, 

 while the quantity of fresh water brought down by the rivers is equal 

 to six, and the quantity lost by evaporation to twelve cubic miles per 

 annum. This would leave an annual excess of sixty-six cubic miles, 

 if the equilibrium was not re-established by an under current flowing 

 into the Atlantic. This hypothesis would appear to have been 

 confirmed by a very curious fact. 



Towards the end of the seventeenth century, a Dutch brig, pursued 

 by the French corsair Phoenix, was overhauled between Tangier and 

 Tarifa, and seemed to be sunk by a single broadside ; but, in place of 

 foundering and going down, the brig, being freighted with a cargo of 

 oil and alcohol, floated between the two Currents, and, drifting towards 

 the west, finally ran aground, after two or three days, in the neigh- 

 bourhood of Tangier, more than twelve miles from the spot where she 

 had disappeared under the waves. She had therefore traversed that 

 distance, drawn by the action of the under current in a direction 

 opposite to that of the surface current. This ascertained fact, added 

 to some recent experiments, lend their support to the opinion which 

 admits of the existence of an outward current through the Straits of 

 Gibraltar. Dr. Maury quotes an extract from the " log " of Lieute- 

 nant Temple, of the United States Navy, bearing the same inference. 

 At noon on the 8th of March, 1855, the ship Levant stood into 

 Almeria Bay, where many ships were waiting for a chance to get 

 westwards. Here he was told that at least a thousand sail were 

 waiting between the bay and Gibraltar, " some of them having got 

 as far as Malaga only to be swept back again. Indeed," he adds, " no 

 vessel had been able to get out into the Atlantic for three months 

 past." Supposing this current to run no faster than two knots an 

 hour, and assuming its depth to be four hundred feet only, and its 

 width seven miles, and that it contained the average proportion of 

 solid matter, estimated at one-thirtieth, it appears that salt enough to 

 make eighty-eight cubic miles of solid matter were carried into the 

 Mediterranean in those ninety days. " Now," continues Dr. Maury, 

 " unless there were some escape for all this solid matter which has 

 been running into the sea, not for ninety days, but for ages, it is very 



