82 GUIDEBOOK OF THE WESTERN UNITED STATES. 
and found numerous stone hammers. It was evident that the work- 
ings were of great antiquity. 
The ruins of the old pueblo of San Marcos stand a sane distance 
north of Los Cerrillos. 
At Waldo the branch railway from Madrid joins the main line. 
West of Waldo the route crosses a thick body of Mancos shale, dipping 
mostly eastward. Near milepost 858, about 4 miles 
west of Waldo, the Dakota and associated sandstones 
and shales are brought up in regular succession from 
under the shales, and they present excellent expo- 
sures not far from the railway. The main mass of sandstone, which 
rises in a ridge of considerable prominence, is underlain by a thick 
series of sandstone and light-colored clays, believed to be the Morri- 
son formation. These beds are underlain by a 60-foot bed of gypsum, 
which comes to the railroad in a high bluff at milepost 859 and con- 
tinues in sight to the north for nearly a mile. This thick deposit of 
gypsum,’ on account of its snow-white color and the large mass 
exposed, is one of the most conspicuous occurrences of the mineral in 
the Southwest. 
At Rosario siding the cliff of gypsum may be seen to bear off to 
the northeast, and the country for many miles west of that place is 
occupied by the sands, gravels, and loams of the formation known 
as the Santa Fe marl, which is of late Tertiary age. There are con- 
spicuous exposures of this formation all along the slopes of the valley 
of Galisteo Creek, past Domingo station, to the Rio Grande. The 
beds lie nearly level and are mostly carved into badland forms. In 
some of the mesas in view far to the northeast these marls are over- 
lain by some thick sheets of black lava (basalt), which were poured 
out over the plain before the valleys had been excavated as deep as 
they are at present. 
By looking up the Rio Grande from the mouth of Galisteo Creek, 
which is 2 miles west of Domingo, the traveler may discern White 
Rock Canyon, through which the river flows for sev- 
pce eral miles and in which it is joined on the west by 
Pajarita and Frijole (free-ho’lay) creeks. In the deep 
canyons of these creeks are some of the most exten- 
sive and remarkable cliff dwellings in the West. The rock of the 
canyon walls is a volcanic tuff of very massive structure and only 
moderate hardness. This great body of tuff lies against the east 
flank of the Valle Grande (vahl’yay grahn’day) Mountains, which rise 
prominently 20 miles to the northwest. In the canyon walls this 
Waldo. 
Elevation 5,606 feet. 
Kansas City 869 miles. 
Kansas paps 881 oot 
: * Gypsum < consists of calcium ee is prepared by heating gypsum to a mod- 
erately high temperature to ute off the 
Hs is the source of plaster of Paris, which combined water and grinding the result- 
used ly in the arts and which | ing mass to a fine powder. 
