ROUTE NEAR THE THIRTY-SECOND PARALLEL. 23 
ROUTE NEAR THE THIRTY-SECOND PARALLEL OF NORTH LATITUDE. 
Among the considerations which determine the general position of the route near the 32d 
parallel, are the low elevation of the mountain passes in this latitude, and their favorable 
topographical features, as well as those of the table-lands, extending over more than 1,000 
miles of the route; the favorable character of the surface generally, on the route, by which the 
most costly item of construction in railroads, the formation of the road-bed, is, in a great 
measure, avoided ; the shortness of the line, 1,600 miles, from the navigable waters of the Mis- 
sissippi to the Pacific, and the temperate climate on the elevated portions in this southern 
latitude. 
The explorations made upon this route are, from Preston, on Red river, to the Rio Grande, 
by Capt. John Pope, Topographical Engineers; from the Rio Grande, near Fort Fillmore, to 
the Pimas villages, on the Gila, by Lieut. John G. Parke, Topographical Engineers. From 
the Pimas villages to the mouth of the Gila, the reconnaissance in New Mexico and California 
of Major W. H. Emory, Topographical Engineers, in 1846, has been used; and from the 
mouth of the Gila to San Francisco, the exploration of Lieut. R. 8. Williamson, Topographical 
Engineers, has furnished the data. 
Fulton, on the Red river, about 150 miles from the Mississippi, may be considered the 
eastern terminus of the route, although the examination of Capt. Pope extends only to Pres- 
ton, 133 miles further west. A direct line from Fulton to the point on the eastern border of 
the Llano Estacado selected by Capt. Pope for crossing it, would give more favorable ground 
than that traversed by him between Preston and this point; the latter in a distance of 352 miles 
gives generally easy grades and cheap construction through a country alternately wooded and 
open, abundantly supplied with water and fuel, and with forest growth suitable for ties and 
lumber for two-thirds of the length. From Fulton to the eastern border of the Llano Esta- 
cado is 485 miles, 370 of which are wooded. 
The exploration of Capt. Pope comprised three distinct belts of country, the first of which 
has been just described above. The second is the Llano Estacado, whose mean elevation is 
4,500 feet, the smooth surface of which along the route proposed, 125 miles from the eastern 
border to the Pecos river, presents in this respect great facilities for the construction of a 
railroad. It is, however, at certain seasons of the year destitute of water, is scantily supplied 
with grass, and not a single tree is to be seen upon it. Its geological formation is such as to 
render the success of obtaining water by artesian wells, at moderate depths, highly probable. 
During, and for some time subsequent to the rainy season, there are here, as on most other 
arid plains, numerous ponds, the contents of which might be collected in reservoirs; but the 
distance from the Colorado Springs to the Pecos, 125 miles, is not so great as to form a serious 
obstacle to the working of a railroad. 
Between the Pecos and the Rio Grande, 163 miles, three mountain chains rise from the 
table-lands, the Guadalupe, Hueco, and Organ mountains. The Guadalupe mountain is 
crossed without a tunnel, elevation of summit 5,717 feet, and with a grade of 108 feet to the 
mile for 22 miles. A high viaduct and heavy cutting and filling for three miles near the 
summit, form the costly and difficult part of the pass. The Waco Pass is still more favora- 
ble, the greatest grade being about 80 feet to the mile; the elevation of the summit, 4,812 
feet. The Organ mountain is turned just before reaching the Rio Grande at Molino and El 
Paso. 
A peculiarity of the mountains in the western part of the continent, in this and other lati- 
tudes, is, that they have no intervening deep secondary valleys between the main chain and 
the plains. Over the usually uniform and smooth surface of these last, the general elevation 
of which, between the Pecos and the Rio Grande, is from 4,000 to 4,500 feet, the valley of the 
Rio Grande is attained near Molino, at an elevation of 3,830 feet, and at a distance of 787 
miles from Fulton. 
