416 THE RIO PECOS. Book II. 
and our animals had had only the dry haulm of the previous 
year ; low moist places, and the bottoms immediately round 
the springs, had been the only exceptions. But now, as we 
approached the valley of the Pecos, an entire change took 
place in the scene. On the 31st of May we arrived at a 
plain covered with grass and flowers, and surrounded by 
regularly-formed table-mountains. The grass and flowers 
were so thick and high, that our horses had difficulty in 
making their way through, and the sweetest perfume, prin- 
cipally of the superb american centaurea, filled the 
atmosphere. This transition to a more advanced season 
was not caused by any difference in the level above the 
sea, but was the result of heavy rains, which had not fallen 
more to the west. From hence eastwards to Texas the 
steppe was in its most gorgeous beauty. 
We reached the river Pecos on the 1st of June, and con- 
tinued our journey for three days along its course, 
athough the road runs occasionally at some distance from 
it, and is even separated by isolated tabular mountains. 
The sides of the valley are broken up by parallel and 
other valleys branching from it. The higher ground 
consists without exception of flat mountains, which on each 
side unite, forming a horizontal table-land of limestone. 
The valley itself is narrow, irregular, full of turns and 
windings ; the stream flows in a deep bed between steep 
clay banks, so that you may come close to it without per- 
ceiving it. For many miles the water is beyond the reach 
of animals, the banks being so perpendicular that they fall 
into it and are carried away by the current. Willows, 
poplars and oaks occur along the stream; but they grow 
chiefly below the banks, on a level with the water, on 
narrow strips of ground bordering the river ; while their 
tops, barely rising above the chasm, look like bushes, and 
