56 



of the Northern Atlantic Ocean, which I have 

 published, by tracing in it with particular care the 

 direction of this retrograde current, that like a 

 river, the bed of which is gradually enlarged, 

 traverses the vast extent of the sea. I flatter my- 

 self that the navigators, who have studied the 

 charts of Jonathan Williams, of Governor Pow~ 

 nail, of Heather, and of Strickland *, will find 

 several objects in mine worthy of their attention. 

 Independent of the observations I have made 

 during six voyages, namely, from Spain to Cuma- 

 na, from Cumana to the Havannah, from the Isle 

 of Cuba to Carthagena in America, from Vera 

 Cruz to the Havannah, from this port to Phila- 

 delphia, and from Philadelphia to the coasts of 

 France, I have collected in this map all that my 

 laborious and active exertions could discover in 

 the journals of such authors 3 as have been able 

 to make use of astronomical means to determine 

 the effect of the currents. I have indicated also 

 the latitudes, in which the motion of the waters 

 is not constantly perceived ; for in the same man- 

 ner as the northern limit of the current of the tro- 



dip of the magnetic needle, the lines without variation, the in- 

 tensity of the magnetic forces, the stripes of floating sea weeds, 

 and other phenomena which interest physical geography. 



N.B. This chart, not yet engraved, will be published in 

 the succeeding volumes. 



* Amer. Trans, vol. ii, p. 328 ; vol. iii, p. 82 and 194 j 

 vol. v, p. 90; and an interesting essay on the currents, by 

 Mr. Delametherie. Journ. de Phys. 1808, t. 67, p. 91. 



