240 



shewn that previously to undertaking any la^ 

 bours on either of those points, they ought all 

 to be examined. It is only by investigating an 

 hydraulic problem in its greatest generality, 

 that it can be advantageously solved. Since I 

 left the New Continent no barometric measure 

 or geodesic levelling has been executed to de- 

 termine the lines of elevation which the pro- 

 jected canals ought to traverse. The different 

 works that have appeared during the war of in- 

 dependence of the Spanish colonies, are confined 

 to the same ideas * which I published in 1 800 - 9 



* I except the useful information given by Mr. Davis Ro- 

 binson, on the anchorage of Huasacualco, Rio San Juan and 

 Panama. Memoirs on the Mexican Revolution, 1821, p. 263. 

 (See also Edinb. Rev., Jan. 1810. Walton in the Colonial 

 Journal, 1817, March and June. Bibl. Universelle de Geneve, 

 Jan. 1823, p. 47 ; Bibliotica Americana, Vol. i, p. 115— 129.) 

 " The bar at the mouth of the Rio Huasacualco has 23 feet 

 of water ; there is good anchorage, and the port can admit 

 the largest ships. The bar of the Rio San Juan, on the 

 eastern coast of Nicaragua, has 12 feet of water j on one 

 point only there is a narrow pass 25 feet deep. In the Rio 

 San Juan there is from 4 to 6 fathoms, and in the lake of 

 Nicaragua from 3 to 8, English measure. The Rio San 

 Juan is navigable for brigs and sloops." Mr. Davis Robin- 

 son also says " the western coast of Nicaragua is not so 

 stormy as it was represented to me during my navigation in 

 the South Sea, and a canal issuing at Panama would have the 

 great disadvantage of being contiuued at a distance of two 

 leagues in the sea, because there are only some feet of water 

 as far as the isles Flamengo and Perico." 



