Mr. Talledo, and a skilful pilot, Mr. Alvarez, were appointed 

 in 1804, to take the plan of the Magdalena from the mouth 

 as far as Honda. I know, that they made use, like me, of 

 sextants, and artificial horizons ; but I am ignorant whether 

 they were also furnished with chronometers. The map of the 

 province of Carthagena by Mr. Talledo is the result of these 

 long and useful operations. I had marked on the drawing, 

 copies of which were left at New Grenada, a table of latitudes 

 and longitudes, determined between Turbaco and Santa-Fe 

 de Bogota. In examining these particular points on Mr. 

 T alledo's map, the following comparison is the result : 



PLACES. 

 The longitudes are re- 

 duced to the Meri- 

 dian of la Popa de 

 Cartagena de Indias, 

 which is 1' 25" east 

 Q f the port. 



Turbaco 



Mahates 



Island of Cotoreo. 



Pinto 



Mompox 



Eadillas (Vadillo) 

 Island of Bruxas. 



Carare 



Nare 



MAP 



of Mr. de Humboldt, 

 drawn at Santa-Fe, 

 in 1801. 



Lat. 



9° 25' 

 9 14 

 7 58 

 6 55 



6 11 



Long. 

 0° 6' 



0 22 



1 39 



0 58 J 



8 

 41 



42 

 5 

 3 



MAP 



of Mr.TALLEDO, taken 

 in 1804. 



Lat. 



9° 25' 

 9 15 

 7 57 



6 55 



6 11 



Long. 



37 



58 



39 

 4 J 



M 



This agreement in the results is so much tbe more remark- 

 able, as it comprises every point of which I fixed the longi- 

 tude from Turbaco to Nare. Does it prove the exactness of 

 my labours ? or has Mr. Talledo (without any indication of it 

 on his map) preferred my observations to his own I If the 

 latter be the case, I regret that he adopted calculations made 

 provisionally in 1801, instead of the positions published by 



