344 THE PHYSICAL GEOGRAPHY OF THE SEA. 



990. There is another circumstance which is worthy of notice 

 in this connection, as illustrative of the accuracy of the knowledge 

 which these investigations afford concerning the force, set, and di- 

 rection both of winds and currents, and it is this : 



991. I had computed the detour which these vessels would 

 have to make, on account of adverse winds, between New York 

 and their place of crossing the equator. The whole distance, in- 

 cluding detour, to be sailed to reach this crossing at that season 

 of the year, was, according to calculation, 4115 miles. The " Gil- 

 pin" and the " Hazard'' only kept an account of the distance act- 

 ually sailed ; the former reaching the equator after sailing 4099 

 miles, the latter 4077 ; thus accomplishing that part of the voy- 

 age by sailing, the one within thirty-eight, the other within six- 

 teen miles of the detour which calculation showed they would be 

 compelled to make on account of head-winds. With his way 

 blazed through the forest, the most experienced backwoodsman 

 would have to make a detour greater than this on account of 

 floods in the rivers. Am I far wrong, therefore, when I say that 

 the present state of our knowledge with regard to the physical 

 geography of the sea has enabled the navigator to blaze his way 

 among the winds and currents of the sea, and so mark his path 

 that others, using his signs as finger-boards, may follow in the 

 same track ? 



