INTRODUCTION. 



Navigation is of the first importance to the 

 improvement and perfecting of the species, in spread- 

 ing, by emigration, the superior varieties of man, and 

 diffusing the arts and sciences over the world ; in pro- 

 moting industry, by facilitating the transfer of com- 

 modity through nmnberless channels from where it 

 is not, to where it is reqiured ; and in bearing the 

 products of those most fertile but unwholesome por- 

 tions of the earth, to others more congenial to the 

 existence of the varieties of man susceptible of liigh 

 improvement : Water being the general medimn of 

 action, — fluidity or conveyance by water, almost as 

 necessary to civilized hfe as it is to organic Hfe, in 

 bearing the molecules forwai*d in theii* vital com'ses, 

 and in floating the pabulimi (the raw material) from 

 the soil through the H^ing canals to the manufacto- 

 ries of assimilized matter, and thence to the points 

 of adaptation. 



A 



