WHIRLPOOLS 



unusually large wave may sweep the weed down thirty 

 or more feet under the surface, in which case the 

 increased pressure will weaken the walls of the bladders 

 so that they are deflated and cannot rise again. The weed 

 is affected by changing temperatures and is thickest in 

 August. 



The bladders are truly amazing devices — tiny "life- 

 belts" which, in their untold millions, literally sustain the 

 life which teems in the vast Sargasso archipelago, holding 

 up the colossal tonnage of its floating islands. 



The phrase "wheels within wheels", which applies to 

 the world's oceans in all kinds of ways, is peculiarly sig- 

 nificant regarding the Sargasso. For it is a slowly spinning 

 wheel containing within it innumerable smaller ones — 

 miniature whirlpools at the junctions of the numerous 

 channels of clear water which lace and interlace the 

 floating weed. The channels are really streams of water, 

 running in many directions, and wherever they meet, 

 small whirlpools are formed which are worthy of the 

 name, for they are often swift enough to be dangerous 

 to small craft. 



There can be no doubt that the Sargasso Sea is chang- 

 ing its position. Maps of eighty or one hundred years ago 

 show that the weed was met within seven degrees north 

 of the equator, and in fifteen degrees W. longitude. 

 But Sargassum is not seen today within six hundred miles 

 of these positions. The weeds, which migrated as indi- 

 viduals across hundreds of miles of ocean and formed an 

 enormous colony, have been moving as a colony ever 

 since. Although large stretches of the whirlpool are still 

 unexplored, and very little is known about such areas, 

 there are now trade routes right through the heart of the 

 Sargasso Sea, mostly traversed by battleships and tramp 

 steamers, for passenger services very rarely pass through 

 it. 



Some writers have described the Sargasso as resembling 

 a vast garden, full of ever-multiplying weeds. The 



lOI 



