346 



MEXICO, CENTRAL AMERICA, WEST INDIES. 



with huge blocks, islands broken into reefs, reefs piled up into islands. The 

 "great hurricane" of October 10, 1786, levelled cities, wrecked fleets, and — 



" -Amid the common woe, 

 Reconciled the French and English foe" — 



who were preparing to cut each others' throats. 



Temperature, Marine Flora and Fauna. 



Swirling round the "West Indian basin, as in a seething cauldron, the inner 

 waters are necessarily warmer, and, owing to the greater evaporation, also 



Fig. 162. — Deep-Sea Tempeeatitbes in the Atlantic and West India Watees. 



Scale 1 : 27.fion nno. 



^^■^< 



West oF G re 



620 Miles. 



relatively more saline than those of the open sea. But the contrast in tempera- 

 ture is observed chiefly at the lower depths, as is also the case in the European 

 Mediterranean. At depths of 700 or 800 fathoms the Atlantic has a temperature 

 of about 40° Fahr., which is the same as that of Bartlett's trough in the Caribbean 

 Sea at over 3,000 fathoms. But at such a depth in the Atlantic the temperature 

 descends to 37°, 35°, and even 33° Fahr. 



The West Indian waters are remarkable for the extreme abundance of tlie 

 species of sargasso known by the name of "tropical grapes." It drifts for 



