1,200 miles, without the advantage of artificially prepared roads.
Rivers.—Mexico, on account of the narrow form of the continent, which prevents the collection of a great mass of water, contains very few navigable streams, the principal ones being the Coatzacoalcos and Panuco Rivers. There are sand-bars at the mouths of many of the rivers, on which not more than three or four feet of water is to be found at low tide. Several streams could be made navigable at comparatively small expense. This fact would apply especially to the Rio de Santiago, the longest river in the Republic, according to Humboldt, who states that it is as long as the Elbe or Rhône, and that the grain from the States of Guanajuato and Jalisco could be thus transported to the western coast.
The following list gives the names and lengths of the principal rivers in Mexico:
| Miles. | Miles. | ||
| Rio de Santiago | 542 | Rio Panuco | 286 |
| Rio de las Balzas | 418 | Rio de Sinaloa | 277 |
| Rio Yaqui | 338 | Rio de Ures | 208 |
| Rio Conchos | 338 | Rio de Culiacan | 156 |
| Rio de Grijalva | 344 | Rio de Goatzacoalcos | 112 |
| Rio Usumasinta | 341 |
Lakes.—There are many lakes on the Mexican plateau, most of which are extensive shallow lagoons, as in the valleys of Mexico and Parras. They are only the remains of large basins of water that formerly existed on the high plains of the Cordillera. The majority of these lakes have no outlet, and are accordingly filled with salt water. Owing to rapid evaporation, their surface has diminished appreciably since the time of the Spanish Conquest.
The Lagoon (laguna) of Terminos, on the coast of the Gulf of Campeche, is the largest in Mexico, but it is an arm of the sea, rather than a lake.
