378 New Mexico and California. 
aving crossed the Arkansas, I met with the first rocks again, on the 
lle springs of Cimarron,” (468 miles ;) it was a sandy limestone 
ab common sandstone. 
- Six miles-west of the Crossing of Cimarron, (500 miles from Inde- 
pendence,) light bluffs rise in the prairie, of a yellow, reddish, and 
too sendatone, combined with lime and argile. 
‘A few miles beyond them, a large isolated mountain of boulders stands 
sandstone pr vailed. 
On Ra eae creek I met for the first time with amygda aloidal 
basalt, a bl heavy, basaltic rock, .with a great many irregular, ve- 
ae Ete Ra: are generally hollow—but some times, filled with 
neces, with olivine. This rock is very common 
throughoat the hah mountains of Mexico. It occurs in irregular mass- 
l 
On _ creek, and Whetstone creek, amygdaloidal basalt with un- 
derlying sandstone was fou nd. 
In going from there to ‘Point of Rocks,” (600 miles,) extensive 
strata of a yellow, compact quarizose sandstone were passed, dipping 
gently towards the east. Point of uae itself, a spur of the western 
—— is a mass of syenite. 
e twelve miles beyond it, rises a hill j in the plains, composed of 
sation black basalt, with underlying white sandstone. 
he bed and bluffs of the Rio Golarad 0 and Ocaté creek, (627 
miles, ) Sime formed by quartzose sandsto 
Th mound, an isolated iaeeeesia in ithe high plain, consists 
of | va black, and spotted basalt, rising in columnar s 
On Wolf creek, (664 miles,) the amygdaloidal basalt and quartzose 
sandstone reappeared, both in horizontal — te 
Reaching the Gallinas creek, near Las Vegas, (690 mil les) Im aly 
after a long interval, with limestone a again. It was a dark blue, with | 
casts of Inoceramus of the cretaceous 
From here we penetrated into the very heart of the mountains. At 
first we pias with sandstone wes, common and quartzose, and of va- 
rious color: 4 
Near San Sign, (707 miles,) a coarse conglomerate was found of 
decomposed granite, sandstone, and lime; and large blocks of decom- 
ae — lined the Pecos river, opposite the old Pecos village, 
roAn _ canon eatin from =e oe Santa Fe, at. first sandstone was 
found, common, quartz reous, of various colors and 
Ainion ons, till about fifieen 1 peice from Santa Fe, granite in situ apenas 
continues all the way to Santa Fe. Near where I met for the 
