SOUTHERN PACIFIC LINES 197 
sands containing some moisture, and also a system of wide-spreading 
lateral roots that quickly absorb water near the surface when there is 
rainfall. Creosote bush, iron wood, paloverde, ocotillo, grasses, and 
scattered cacti of several kinds are the more noticeable plants in the 
valleys and along the dry mountain slopes. 
The topography is of the Basin and Range type, with high, bare 
rocky ridges, mostly narrow, separated by wide, flat valleys. The 
larger features trend north and south, although there are many local 
exceptions to this trend. The valleys range from about 3,000 feet 
above sea level in the northeast to 250 feet in the Yuma Desert. The 
mountains are bare and desolate, and the broad desert valleys with 
terrifying scarcity of water seem formidable to travelers. For many 
persons, however, the region possesses an intense interest and charm— 
often referred to as the lure of the desert. 
MAIN LINE, PICACHO TO PHOENIX AND WELLTON, ARIZ. 
The line from Picacho to Wellton by way of Phoenix (turn to sheet 
23) was built in 1925 and 1926 at a cost of $15,600,000, in order to 
pass through the great irrigation district of the Gila 
Picacho. (he’la) and Salt Rivers. It is 42 miles longer than the 
Elevation 1621 feet. old line but has the advantages of better grades, fewer 
miles. "~~ eurves, and long tangents, which almost compensate 
for the detour. The Gila River is crossed twice, one 
' bridge being 5,000 feet long and the other 3,800 feet. 
This route leaves the old main line at a switch tower a mile west of 
Picacho siding and goes north across the wide alluvial plain to the 
Coolidge. Gila River, 20 miles distant. It passes through the 
cietuigt tu sidings of Peak. Topaz, and Randolph and the town 
Population 1,100. Of Coolidge in this interval and also crosses the great 
sae ac 1,564 ditch that carries water from the Gila River to Casa 
Grande and other irrigation settlements to the west- 
ward. This water conserved by the Coolidge Dam, on the Gila River 
in the mountains 50 miles above Florence, is let out into the river as 
required and deflected into the main canal near Florence. (See p. 210.) 
About 40,000 acres of the land to be irrigated is in the Gila River 
Indian Reservation, and the remainder of the water is available for 
settlers outside, who have taken up much of the land and are 
cotton, lettuce, and other crops with satisfactory results. 
Two miles beyond Coolidge the ruins of Casa Grande are in sight, 
not far west of the railroad. For many years they had no protection 
against the weather, but finally after some restorations a roof was 
erected to protect the ruins from rain and in some measure from wind- 
blown sand, a powerful erosive agent in regions of dry climate. (See 
pl. 24, A.) 
