WEST INDIAN HURRICANES. 345 



SucL. proportions are difficult to grasp, for they represent a moving mass equal 

 to about 300,000 rivers such, as the Mississippi. Yet they are still far inferior 

 to the prodigious volume of relatively tepid water spread over the surface of the 

 North Atlantic and Arctic Oceans. In fact, the Gulf ^tream issuing from Florida 

 Strait supplies only a small portion of those tepid waters whose influence is felt 

 as far east as Novaya Zeralia. The main supply comes from that portion of the 

 equatorial current which is deflected northwards by the barrier of the West India 

 Islands, and which is joined by the Gulf Stream south of the Bermudas. 



Atmospheric Currents — Hurricanes, 



Where they enter the Caribbean Sea the atmospheric have not quite tte same 

 mean direction as the marine currents. These set mainly from south-east to 

 north-west, whereas the trade winds blow nearly always from the east or north- 

 east. The deviations occur especially in the neighbourhood of the coasts. The 

 north-east trade, which on the Venezuelan mainland maintains its normal course, 

 veers round to the east along the Central American seaboard, and reaches the 

 shores of Jamaica and Cuba from the south-east. But the greatest disturbance 

 in the regular aerial system is caused by the sudden squalls from the north, which 

 sweep from the Polar regions down the Mississippi valley to the Gulf. 



The American Mediterranean is also exposed to hurricanes, whose very Carib 

 name (hurakan, huiranvucan) shows that the European navigators regarded these 

 atmospheric disturbances as peculiar to the West Indian waters. Their main 

 direction about coincides with the insular chain of the Lesser Antilles and 

 Bahamas ; but after reaching the extreme convexity of their curvature in the 

 south-eastern region of the United States, they are deflected north-eastwards, 

 arriving in a somewhat exhausted state on the European seaboard. 



In the West Indian waters their normal direction is merged in that of the 

 magnetic needle without declination, passing from the Guianas through St. 

 Vincent and Puerto Rico towards South Carolina, and crossing the Caribbean 

 Sea in a period varying from two to four days. The parts of the American 

 Mediterranean most remote from this main axis are also the least exposed to the 

 fury of the hurricanes. But the oft-repeated statement that Trinidad, the 

 southern Dutch islands, the mainland and isthmian inlets from Honduras to 

 Vera Cruz lie beyond the cyclonic zone is not correct, as shown by the wreckage 

 strewn over the roadsteads of Panama and Colon, and the destruction of Blew- 

 fields, thoiigh these disasters are certainly rare. 



The hurricanes are also said to occur only at the end of summer or beginning 

 of autumn, when the heated surface of South America attracts the cooler and 

 denser air of the northern continent. But although most frequent in August, 

 and generally between July and October, such disturbances have also been 

 recorded at other times. Few years pass without some disaster taking place at 

 one point or another of the normal storm zone. Houses have been uprooted like 

 trees, fortresses have been demolished, ships carried far inland, plantations strewn 



