THE GULF STREAM. 29 



it is true, and their routes cannot Le ascertained. But knowing 

 where they were cast, and seeing where they are found, some 

 idea may be formed as to their course. Straight lines may at 

 least be drawn, showing the shortest distance from the beginning 

 to the end of their voyage, with the time elapsed. Captain 

 Becher, E.N., has prepared a chart representing in this way the 

 tracks of more than one hundred bottles. From this chart it 

 appears that the waters from every quarter of the Atlantic tend 

 toward the Gulf of Mexico and its stream. Bottles cast into the sea 

 midway between the Old and the New Worlds, near the coasts of 

 Europe, Africa, and America, at the extreme north or farthest 

 south, have been found either in the West Indies, on the British 

 Isles, or Avithin the well-known range of Gulf Stream waters. 



87. Tlieir drift. — Of two cast out together in south latitude on 

 the coast of Africa, one was found on the island of Trinidad ; the 

 other on Guernsey, in the English Channel. In the absence of 

 positive information on the subject, the circumstantial evidence 

 that the latter performed the tour of the Gulf is all but conclu- 

 sive. And there is reason to suppose that some of the bottles of 

 the gallant captain's chart have also performed the tour of the Gulf 

 Stream ; then, without being cast ashore, have returned with the 

 drift along the coast of Africa into the intertropical region ; 

 thence through the Caribbean Sea, and so on with the Gulf 

 Stream again. (Plate VI.) Another bottle, said to be thrown over 

 oif Cape Horn by an American ship-master in 1837, was after- 

 wards picked up on the coast of Ireland. An inspection of the 

 chart, and of the drift of the other bottles, seems to force the con- 

 clusion that this bottle too went even from that remote region to 

 the so-called higher level of the Gulf Stream reservoir. 



88. The Sargasso Sea. — Midway the Atlantic, in the triangular 

 space between the Azores, Canaries, and the Cape de Verd Islands, 

 is the great Sargasso Sea. (Plate YI.) Covering an area equal 

 in extent to the Mississippi Valley, it is so thickly matted over 

 with Gulf weed (Fucus natans) that the speed of vessels passing 

 through it is often much retarded. When the companions of 

 Columbus saw it, they thought it marked the limits of naviga- 

 tion, and became alarmed. To the eye, at a little distance, it 

 seems substantial enough to walk upon. Patches of the weed 

 are generally to be seen floating along the outer edge of the Gulf 

 Stream. The sea- weed always " tails to" a steady or a constant 

 wind, so that it sei-^-es the mariner as a sort of marine anemo- 



