414 



they say pompously here, the fortress of the 

 frontier, far from being, as father Caulin affirms, 

 in 0° 20' of latitude, or in 0° 53', where La 

 Cruz and Surville, (who are the official geogra- 

 phers of the real Expedition de Limites) have 

 thought proper to fix it, is in 1° 53' 42". The 

 equator therefore does not pass to the north of 

 the little Portugueze fort of San Jose da Mara- 

 bitannas, as it has been marked* in all the maps 



in it's real position. It is expressly said in an advertisement 

 added to the map of the Rio Negro by Jose Joaquim Victorio 

 da Costa, Jose Simoens de Carvalho, and Manoel de Gama 

 Lobo, that whatever relates to Spanish Guyana is taken 

 from the map of the Voyage de Deports, which was traced by 

 Mr. Poirson, from my observations made on the spot, (See 

 my Obs. Astr., vol. i, p. 238.) The Portugueze had the 

 habit, as I have said above (p. 364-5) of extending their 

 frontiers toward the north ; and perhaps observations, made 

 at the forts of San Gabriel das Cochoeiras and San Jose da 

 Maribitanuas, had enlightened the Portugueze astronomers, 

 before my voyage, respecting the real situation of San Carlos. 

 In the map of Requena, traced in 1783, and founded on 

 Portugueze materials, it is marked two degrees seventeen 

 minutes. It is even twenty-four minutes in fault, toward the 

 north. The two hundred and thirty-five points, of which I 

 fixed the astronomical situation by my own observations in 

 the inland country, were calculated and published for the first 

 time by Mr. Oltmans in 1808 (consequently a year before the 

 publication of my Recuell d' Observations Astronomiques), in 

 a memoir entitled Conspectus Long, et Lat. per Decursum 

 Annorum 1799 — 180*4, in Plaga equinoctiole astionomice ofr- 

 servatorum. 



* Did d'Anville alone r guess, in 1750, that the equator 



