570 ADAPTATION OF THE COUNTRY 
quantity is small; and the latter is rather a grazing than an 
agricultural district. 
In about the latitude of 31° the water-courses of northern 
Sonora begin to appear, and with them the luxuriant valleys, 
through several of which I found my way across the country 
to the Gulf. Those streams, though denominated rivers, 
would scarcely be characterized as such in the United States ; 
the term rivulet would be far more appropriate. 
As regards the construction of a railway through Texas, 
the country is entirely open and generally level. The first 
elevation to be passed, following the parallel of 32 degrees, is 
Castle Mountain, about ten miles east of the river Pecos, 
which may be avoided by diverging either to the north or 
south. After crossing the Pecos, the route should be south 
of the Guadalupe range of mountains, a lofty and continuous 
chain, which, coming from the north, where it is united by the 
Sacramento range, terminates abruptly in about 31° 50’ north 
latitude. South of these mountains, the country is quite open 
and apparently level, with isolated mountains at long inter- 
vals, but no connected chains. or the hundred miles which 
we followed the Pecos, there were neither hills nor mountains, 
and this character of country extends to the Rio Grande. <A 
mountain chain, called the ‘ Sierra de los Organos,” crosses this 
river near El Paso, and extends north for some eighty miles. 
These mountains may easily be passed through where the river 
has opened a way for itself near Hl Paso, and again about forty 
miles to the north. But surveys must determine whether, in 
coming from the Mississippi, a route near the parallel of 32 
degrees, or along the Colorado or Canadian rivers, will be more 
practicable. 
After crossing the Rio Grande, should a point north of El 
Paso, between the latitude of 31° 53’ and 32° 20’ be selected, 
there is an open country for more than one hundred miles. 
Some mountain ranges are then to be passed, through easy 
slopes or defiles, and in no case by surmounting them. In fact, 
