314 



MEXICO, CENTEAL MIEEICA, WEST INDIES. 



feet high, so that for an interoceanic canal it would have to be pierced by a 

 tunnel at least seven miles long and high enough to admit the tallest vessels. 



The San Bias (Chepo) cordillera, consisting of gneiss and metamorphic schists, 

 is continued under various names as the Atlantic coast-range as far as the entrance 

 to Uraba Bay, where the isthmus takes the name of Darien. The hilly mass of 

 Gandi (3,000 feet) and Turganti farther on mark the point where the system bends 

 round to the south along the west side of the Rio Atrato, At the Tihule Pass it 

 falls as low as 420 feet, and this site has also been proposed for an interoceanic 

 canal, which would replace an ancient marine strait along the valleys of the Rio 

 Atrato in the east and Rio Tuyra in the west. 



Farther on the cordillera is connected by lateral ridges with the Baudo range, 

 which runs close to the Pacific coast in the direction from north to south for a 



Fig-. 140. COTIESE OF THE RlTER ChAGEES. 



Trom a Spanish Mar» of the first half of the Eighteenth Century. 





^Oc, PESQUE^P&oDE LAS 



^^y^-^'^ ^ ^''^'''^.''^'-^Mzî ^Z^^l^^ 



distance of about 124 miles. The sierra culminates in the Baudo peak (6,000 feet), 

 but it is interrupted by broad depressions, one of which, the Cupica Pass, is only 

 1,000 feet high. The last rising grounds of the plateau die out north of the San 

 Juan estuarj\ 



Rivers, Bays, Islands. 



Apart from the Atrato, only a few lateral affluents of which are comprised in 

 the province of Panama, the isthmus has no large rivers, or, at least, none that 

 send down a large volume excejDt after heavy rains. Many have a considerable 

 course owing to the disposition of their valleys, which run jiarallel with, and not 

 transversely to, the seaboard. But their basins are too narrow to collect any great 

 quantity of surface waters. 



Even the Chagres, a term which, according to Pinart, means " Great River " 

 in the Muoi language, is in ordinary times an insignificant tributary of the Carib- 

 bean Sea. It rises about the centre of the isthmus of Panama, and flows first in 



