16 THE PHYSICAL GEOGRAPHY OF THE SEA. 



which strew the beach or line the shores, portions of every sol- 

 uble ingredient known in nature. Thus impregnated, the laugh- 

 ing, dancing waters come down from the mountains, turning 

 wheels, driving machinery, and serving the manifold purposes 

 of man. At last they find their way into the sea, and so make 

 the lye of the earth brine for the ocean. ' 

 •44. Iron, lime, silver, sulphur, and copper, silex, soda, mag- 

 soud ingredients, ncsia, potash, chloriuc, iodine, bromine, ammonia, 

 are all found in sea- water ; some of them in quantities too minute 

 for the nicest appliances of the best chemists to detect, but which, 

 nevertheless, are elaborated therefrom by physical processes. 



45. By examining the copper that had been a great while on 

 Quantity of silver in the bottom of a ship in Valparaiso, the presence of 

 *^^ '^^- silver, which it obtained from the sea, was detected 

 in it. It was in such quantities as to form the basis of a calcula- 

 tion, by which it would appear that there is held in solution by 

 the sea a quantity of silver sufficient to weigh no less than two 

 hundred million tons, could it all, by any process, be precipitated 

 and collected into bars. 



46. The salts of the sea, as its solid ingredients may be called, 

 Its inhabitants- ^^^ neither be precipitated on the bottom, nor taken 

 their offices. ^p -^j ^-^q yapors, nor returned again by the rains 

 to the land ; and, but for the presence in the sea of certain agents 

 to which has been assigned the task of collecting these ingredients 

 again, in the sea they would have to remain. There, accumu- 

 lating in its waters, they would alter the quality of the brine, in- 

 jure the health of its inhabitants, retard evaporation, change 

 climates, and work endless mischief upon the fauna and the flora 

 of both sea, earth, and air. But in the oceanic machinery all this 

 is prevented by compensations the most beautiful and adjustments 

 the most exquisite. As in the atmosphere the plants are charged 

 with the office of purifying the air by elaborating into vegetable 

 tissue and fibre the impurities which the animals are continually 

 casting into it, so also to the mollusks, to the madrepores, and 

 insects of the sea, has been assigned the office of taking out of its 

 waters and making solid again all this lixiviated matter as fast as 

 the dripping streams and searching rains discharge it into the 

 ocean. 



47. As to the extent and macrnitude of this endless task some 



