262 
LETTERS FROM HIGH LATITUDES. 
sweeps up round the Cape of Good Hope, and crossing 
the Atlantic, twists into the Gulf of Mexico. Here its 
flagging energies are suddenly accelerated in conse¬ 
quence of the narrow limits within which it finds itself 
compressed. So marvellous does the velocity of the 
current now become, so complete its isolation from the 
deep sea bed it traverses, that by the time it issues 
again into the Atlantic, its hitherto diffused and loitering- 
waters are suddenly concentrated into what Lieutenant 
Maury has happily called—“ a river in the ocean,” swifter 
and of greater volume than either the Mississippi or the 
Amazon. Surging forth between the interstices of the 
Bahamas, that stretch like a weir across its mouth, it 
cleaves asunder the Atlantic. So distinct is its indivi¬ 
duality, that one side of a vessel will be scoured by its 
warm indigo-coloured water, while the other is floating 
in the pale, stagnant, weed-encumbered brine of the 
Mar de Sargasso of the Spaniards. It is not only by 
colour, by its temperature, by its motion, that this “ porj 
’Qrceavoio ” is distinguished; its very surface is arched 
upwards some way above the ordinary sea level toward 
the centre, by the lateral pressure of the elastic liquid 
banks between which it flows. Impregnated with the 
