SOUTHERN PACIFIC LINES 223 
North Star, and other gold mines, which at one time, it is claimed, 
yielded nearly $5,000,000 in gold and silver, much of it from very 
high grade ore, some of which assayed as high as $20,000 a ton (Year- 
book of Arizona, 1930). The ore bodies were in veins in voleanic 
rocks (andesites) of Tertiary age. ; 
North from Tyson siding the peaks of the south end of the Castle 
Dome Mountains are conspicuous. They consist of a central core 
of schist, heavily flanked by lavas of Tertiary age. Far to the north 
may be seen the culminating summit, Castle Dome Peak, which is a 
prominent landmark in a region of wide extent, This peak was 
called Bauquiburi by the Indians and was often referred to in the 
narratives of early travel as the Cabeza del Gigante (ca-bay’sa del 
he-gahn’tay, Spanish for head of the giant). There are mines near 
its base on the west slope of the range. 
South of Roll the prominent, sharp Baker Peaks are in view south 
of the Gila River, and beyond them the rugged crest of the Copper 
Roll. Mountains. Roll is a small settlement sustained by 
Elevation 265 feet,  UTigation, using water pumped from sand and gravel 
Population 40.* holding underflow from the river. To the west are 
eans 745 the prominent Muggins Mountains, and to the north 
the west side of the Castle Dome Mountains is con- 
spicuous. The wide river terraces to the west are deeply trenched by 
ar;royos. 
Just west of Roll the railroad line bends southwestward toward the 
Gila River, which is crossed at the north end of Antelope Hill, as 
shown in Plate 33, B. This hill is composed of light-colored arkose 
and arkosic sandstone supposed to be of Tertiary age, of which about 
500 feet is exposed, dipping to the south at a low angle. Other ex- 
posures of the same rock constitute the north end of the Mohawk 
Mountains, as shown in Plate 32, B, the two knobs a mile southwest 
_of Ming siding, and the Baker Peaks, southeast of Ming. The rock 
is quarried extensively at two places near the river. 
After crossing the Gila River the railroad turns to the south- 
southwest and, rising onto the wide upland terrace, here 50 feet above 
the river flat, joins the old main line at Wellton. 
Wellton is a local trading settlement for the cattle and irrigation 
industry and a headquarters for mining interests of the surrounding 
‘elie. country. There is considerable irrigation near by and 
Elevation 258 fer,  10F & few miles west from wells and from ditches taken 
Population 80.* out of the Gila River. The village is situated on a 
New Orleans 1,755 wide desert plain 2 or 3 miles south of the river. 
ot igh mountains are visible on all sides. To the north 
are the Muggins Mountains, an irregular series of high ridges of 
Tertiary volcanic rocks heavily flanked to the east and south by 
conglomerates and other strata of later Tertiary age. Farther north 
