410 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1947 



Since Congress ordered examination of ail possible routes, the ob- 

 vious line of attack was to study each possibility in turn to the point 

 where it eliminated itself from consideration because of lack of water 

 for lockages, too great length, poor terminals, excessive excavation, 

 lack of security, and other applicable reasons. If followed thoroughly 

 and fairly, this procedure should leave for final consideration the best 

 type canal on the best route. To achieve a degree of comparison among 

 all routes a hypothetical canal was initially assumed in each case, with 

 a bottom width of 500 feet and with side slopes of 1 : 1. 



GULF 

 OF 

 TEHU&NTEPSC 



Figure 2. — Engineering and construction studies initially encompassed 22 isthmian 

 routes from Mexico to Colombia. Those named plus two others— the Panama 

 Parallel and Panama Conversion Routes near the present canal — warranted 

 the most study. 



A total of 22 routes was examined, as shown on the map, figure 2. 

 Including practically all of the routes that have been proposed or 

 studied over the past century or more, the list contained some that were 

 readily dropped from consideration as patently impractical, others 

 that required more detailed study, and a few upon which special field 

 work was deemed necessary. Indicative of routes easily eliminated was 

 Tehuantepec in Mexico, which has the advantage of being nearest 

 the United States, but would require 6l^ billion yards of excavation 

 for a sea-level canal and 15 lifts of about 39 feet each for a lock canal. 

 Another even more easily eliminated was Chiriqui in Panama near 

 the Costa Rican border where an even greater yardage would have 



