las, whence it takes a south-west course and receives, at the foot of the Monte de Sal Gemme, the Rio de Nuestra Señora de Dolores, which springs about 1° 30' west of the Rafael, in the Cerro de la Plata; and, thus, receiving the accretions of a number of other streams, it courses onward until it is lost at the head of the Gulf of California. The whole length of the Colorado is estimated at about two hundred and fifty leagues. For about fifty leagues it is navigable by small sea going vessels; and, for about a hundred leagues higher, it may be traversed by large boats. The sea is said to ebb and flow between thirty-five and forty leagues beyond the mouth of this river. The sources of the Arkansas and of the Rio Grande del Norte lie very near those of the Colorado until it unites with the Colorado; so that the waters of the Gulf of Mexico and of the Gulf of California are nearly united by these streams across our continent.
15th. The Rio Gila rises in the Sierra de los Mimbres, and descends to the south, through a small and mountain bound valley until it unites with the Colorado.
IV. Lakes, Lagunes, &c.
1. Timpanogos and Teyugo or Salado.
2. Lagunas de Bavispe, San Martin, de Guzman, de Patos, De Encinillas and de Castilla in the state of Chihuahua.
3. The Laguna de Cayman in the Bolson de Mapimi.
4. The Lakes of Parras and Agua Verde on the west boundary of Coahuila.
5. The Lakes of Charcas, Chairel and Chila in the state of San Luis Potosi.
6. Nine small Soda Lakes in Zacatecas.
7. The large and important Lake of Chapala and others in Jalisco.
8. Pazcuaro, Cuizco, Araron, Huango, Tanguato, and Huaniquio in Michoacan.
9. The five large Lakes of Tezcoco, Chalco, Xochimilco, San Cristoval and Zumpango in the valley of Mexico.
10. The Lakes of Atenco, Coatetilco, and Tenancingo in the valley of Toluca.
11. A number of small ones in Oajaca.
12. The Lakes of Tampico, Catemaco, Alijoyuca, Tenango, Chiapa on the gulf coast or near it.
13. The Lake of Yurirapundaro in Guanajuato.
