22 PHYSICAL GEOGKAPHY OP THE SEA, AND ITS r.lETEOIiOLOGY. 



68. Specimens from the depth o/19,800/ee^. — Lieutenant Brooker, 

 in the " Hancock," has obtained soundings in the North Pacific 

 from the depth of 3300 fathoms, with specimens both of the ooze 

 and the water at the bottom. These have been sent to Professor 

 Ehrenberg of Berlin, for microscopic examination. He has not 

 completed his study of these treasures, but he already reports the 

 discover}- in them of more than one hundred new species of 

 animalculaa. 



CHAPTER II. 



§ 70-147. — THE GULF STREAM. 



70. Its colour. — There is a river in the ocean : in the severest 

 droughts it never fails, and in the mightiest floods it never over- 

 flows; its banks and its bottom are of cold water, while its 

 current is of warm ; it takes its rise in the Gulf of Mexico, and 

 empties into Arctic seas ; this mighty river is the Gulf Stream. 

 There is in the v/orld no other such majestic flow of waters. 

 Its current is more rapid than the Mississippi or the Amazon, and 

 its volume more than a thousand times greater. Its waters, as 

 far out from the gulf as the Carolina coasts, are of indigo blue. 

 They are so distinctly marked that their line of junction with 

 the common sea-water may be traced by the eye. Often one- 

 half of the vessel may be perceived floating in Gulf Stream 

 water, while the other half is in common water of the sea — 

 so sharp is the line, and such the want of affinity between those 

 waters, and such, too, the reluctance, so to speak, on the part 

 of those of the Gulf Stream .to mingle with the littoral waters of 

 the sea. 



71. Soio caused. — At the salt-works of France, and along the 

 shores of the Adriatic, where the "■ scdines'^ are carried on by the 

 process of solar evaporation, there is a series of vats or pools 

 through which the water is passed as it comes from the sea, and 

 is reduced to the briny state. The longer it is exposed to evapo- 

 ration, the Salter it grows, and the deeper is the hue of its blue, 

 until crystallization is about to commence, when the now deep 

 blue water puts on a rcddi.sh tint. Now the water of the Gulf 

 Stream is Salter (§ 102) than the littoral water of the sea through 

 which it Hows, and hence we can account for the deep indigo 

 blue which all navigators observe in Gulf Stream water off the 



