434 VIEWS, &C. PLATEAU OF CAXAMARCA. 



between Atrato and the Bay of Cupica, on the shore of the 

 Pacific, the mountain chain of the Isthmus almost entirely 

 disappears.'* 1 



In the year 1828 and 1829, General Bolivar, at my request, 

 caused the Isthmus between Panama and the mouth of the 

 Rio Chagres to be accurately levelled by Lloyd and Falmarc.f 

 Since that time, other measurements have been executed by 

 intelligent and experienced French engineers, and plans have 

 been drawn out for canals and railways with locks and tunnels. 

 But these measurements have invariably been made in the 

 meridian direction between Porto-bello and Panama, or west- 

 ward from thence, towards Chagres and Cruces. The most 

 important points of the eastern and south-eastern parts of the 

 Isthmus, on both shores, have in the meantime been over- 

 looked. Until those parts shall be described geographically, 

 according to accurate (but easily obtained) chronometrical 

 determinations of latitude and longitude; and hypsometrically, 

 with reference to their superficial conformation, by barome- 

 trical measurements and elevations, I see no reason to alter 

 the views I have always entertained on this subject. Accord- 

 ingly, at the present time (1849), I here repeat the opinion I 

 have often before expressed; viz., that the assertion is ground- 

 less and altogether premature, that the Isthmus of Panama 

 is nnsuited to the formation of an Oeanic Canal — one with 

 fewer sluices than the Caledonian Canal — capable of affording 

 an unimpeded passage, at all seasons of the year, to vessels 

 of that class which sail between New York and Liverpool, and 

 between Chili and California. 



According to examinations, the results of which the Direc- 

 tors of the Deposito Hidrografico of Madrid have caused to 

 be inserted in all their maps since 1809, it appears that on 

 the Antillean shore of the Isthmus, the creek called the 

 Ensenada de Mandinga, stretches so far to the south that its 

 distance from the Pacific shore, eastward of Panama, appears 

 to be only between 4 and 5 German geographical miles (15 to 



* See my Atlas geographique et physique de la Kouv. Espagne, 



pi. iv. and Atlas de la Relation historique, pi. xxii. xxiii.; also my 



Voyage aux regiones equinoxiales du Nouveau Continent, t. iii. 



pp. 117 — 154, and Essai politique sur la royaume de la Nouvellc 



Espagne, t. i. 2nde ed. 1825, pp. 202—248. 



*r Philosophical Transactions of the Royal Soc. of London for the 

 year 1830, pp. 59 -68. 



