10 THE OYSTER. 



ands of tons of gold and silver which, as chemists tell 

 us, the sea holds dissolved in its water, all these are 

 as nothing when compared with these precious wash- 

 ings from the land of all that fits it for supporting life. 



Man will some time assert his dominion over the 

 fishes of the sea, and will learn to send out flocks and 

 herds of domesticated marine animals to pasture and 

 fatten upon the vegetable life of the ocean and to 

 make its vast wealth of food available, but at present 

 we are able to do little more than to snatch a slight 

 tribute from the stream of nutritive material which is 

 flowing down into the ocean, as it comes to temporary 

 rest in the valleys of our great rivers. 



Every one knows the part which these great river- 

 valleys have played in human civilization. In the 

 valley of the Nile, of the Tigris, and of the Ganges 

 we find the most dense populations; here were the 

 great cities of the past; here agriculture and architec- 

 ture were developed, and here art, literature and 

 science had their birth. 



We owe to the great river-valleys, where the natural 

 fertility of the soil has lightened the struggle for 

 bread and has afforded leisure for higher matters, all 

 that is most distinctive of civilized man. 



The Chesapeake Bay is a great river- valley ; not as 

 large as that of the Nile or Ganges, but of enough con- 

 sequence to play an important part in human affairs, 

 and to support in comfort and prosperity a population 

 as great as that of many famous states. It receives 

 the drainage of a vast area of fertile land stretching 



