THE DRIFT OF THE SEA. 249 



the color of the sea, makmg it crimson, brown, black, or white,* 

 according to their own hues. These patches of colored water 

 sometimes extend, especially in the Indian Ocean, as far as the 

 eye can reach. The question, "What produces them?" is one 

 that has elicited much discussion in seafaring circles. The Brus- 

 sels Conference deemed them an object worthy of attention, and 

 recommended special observations w4th regard to them. 



The discolorations of which I speak are no doubt caused by 

 organisms of the sea, but whether w^holly animal or wholly vege- 

 table, or whether sometimes the one and sometimes the other, has 

 not been satisfactorily ascertained. I have had specimen? of the 

 coloring matter sent to me from the pink-stained patches of the 

 sea. They w^ere animalculae w^ell defined. Quantities of slimy, 

 red coloring matter are, at certain seasons of the year, washed 

 up along the shores of the Red Sea, which Dr. Ehrenberg, after an 

 examination under the microscope, pronounces to be a very deli- 

 cate kind of sea weed : from this matter that sea derives its name. 

 So also the Yellow Sea. Along the coasts of China, yellowish col- 

 ored spots are said not to be uncommon. I know of no examina- 

 tion of this coloring matter, however. In the Pacific Ocean I have 

 often observed these discolorations of the sea. Red patches of 

 w^ater are most frequently met with, but I have also observed white 

 or milky appearances, which at night I have know^n greatly to 

 alarm navigators, they taking them for shoals. 



542. These teeming waters bear off through their several chan- 

 nels the surplus heat of the tropics, and disperse it among the 

 icebergs of the Antarctic. See the immense equatorial flow to 

 the east of New Holland. It is bound for the ic}^ barriers of that 

 unknown sea, there to temper climates, grow cool, and return 

 again, refreshing man and beast by the way, either as the Hum- 

 boldt Current, or the ice-bearing current which enters the Atlantic 

 around Cape Horn, and changes into warm again as it enters the 

 Gulf of Guinea. It was owing to this great southern flow from 

 the coral regions that Captain Ross was enabled to penetrate so 

 much farther south than Captain Wilkes, on his voyage to the 



lations of identity with other provinces. The Red Sea and Persian Gulf arc its off- 

 sets." — From Professor Forbes's Paper on the " Distribution of Marine Life." Plate 

 31st, Johnston's Physical Atlas, 2d ed. : Wm. Blackwood & Sons, Edinburgh and 

 London, 1854. . * See Appendix K 



