278 NINTH ANNUAL REPORT OF 



ern side of the Rio Grande, I have never heard. But if the name should 

 occur there, too, as some maps likewise have it, I am almost sure that 

 it has only been used by some Mexican theorist who wanted to convey 

 a general idea of the geography of his country according to his own 

 fancy — that it is not, therefore, a commonly employed term there — and 

 under no consideration could even a fact contrary to this conviction 

 prove any connexion of the Rocky Mountains with the Sierra Madre 

 proper, which, following the direction of the Pacific coast of Mexico, 

 borders the interior table-land of that country towards the low country 

 of Michoacan, Jalisco, Sinaloa, and Sonora. If such a conclusion could 

 be allowed to be drawn from a mere name, it would certainly be as 

 justifiable to prove a connexion, or at least a relation, of the Sierra 

 Madre proper to that chain of" mountains which our geologists now call 

 the San Bernardino chain, but which the old Californians likewise 

 know under the name of Sierra Madre. 



Now as to the Sierra Madre proper, there is a singularity in the 

 natural structure of this marginal chain, which, though by no means 

 uncommon in other similar chains in different parts of the world, is one 

 of the principal causes of the misconstructions of our maps in respect 

 to western and northern Mexico. Nearly all the more considerable 

 rivers which empty into the Gulf of California have their origin on the 

 high plains of the interior table-land — that is to say, on the eastern side 

 of the Sierra Madre — and, bursting through deep and narrow gorges or 

 rents, cross the chain at right angles belbre they come down on a lower 

 terrace of the country, and ultimately into the '■Hierra caliente''' of the 

 coast. This fact is to be seen in the most striking manner on the road 

 from Chihuahua to the rich mining place of Batoseagachic, where the 

 traveller passes, without any ascent, from the high plateau on the eastern 

 side of the Sierra down into the deep country on its western side, 

 through one of these openings; the road coming out on the latter side 

 at an elevation of several thousand feet above the lower country, where 

 he may see the orange and banana, while he is still in the region of the 

 pine-trees and of a northern climate. The water-course at the bottom 

 of the transversal gorge is tributary to the Rio del Fuerte, which 

 empties into the gulf somewhat south of the Rio Yaqui. One of the two 

 principal branches of this latter river, the Rio de Papigochic or Con- 

 ception, shows a similar phenomenon. For nearly a hundred miles it 

 runs along the eastern side of the sierra in a northerly direction, through 

 the beautiful savannas of the western table-land of Chihuahua, passing 

 many fine little towns, until at last it makes a sudden turn to the west, 

 enters a gap in the mountains so narrow that it is scarcely perceptible 

 in the landscape, and through it dashes down into the deep country on 

 the western side of the chain. One of these two passages must be had 

 in view by the projectors of the railroad I'rom El Paso or the Presidio 

 del Norte to Guaymas, for which Santa Anna has lately given a con- 

 cession. As geographers, however, have not understood this character 

 of the chain, they have placed it so far to the east of its real situation 

 as to get it on the eastern side of the origin of the rivers of Sonora and 

 Sinaloa. 



At the same time there are some reasons to suspect that the astro- 

 nomical Dositions of the interior of these two States are likewise too far 



