506 Notes on the Pyrenees. 
sward crowning the outlying hills effects a gradation with the 
plains below, the dark tint of the bare rock on the acclivities 
diminishes the intensity of the shades, while the eternal snows 
lose their lofty summits in the passing clouds, 
The disposition generally assumed by the alpine limestone 
is that of 
gentle slopes i in the direction of its inclination, with 
bleak precipices on the opposite side, continued oftentimes for 
a great distance in the line of the direction of the strata; in 
the pass between Simoux and Alet, in the Eastern Pyrenees, 
the strata descend in a line parallel to the perpendicular aspect 
to the banks of the river Aude. The transition rocks present 
sometimes the same features, particularly in the mountains of 
the Corbiéres : in the latter chain, above the town of St. Paul, 
the uniformity of disposition is broken by a shift allowing a 
passage through the chain. The valley of the Corbieres is 
reached from Mirepoix through a glen, in which the road 
descends for more than a league at a considerable angle of in- 
clination ; it is rendered safer by piled walls of stones. Huge 
precipices are seen below, and one or two caverns are met 
with in the ascent, from which we drove numerous pipistrelles, 
notwithstanding the proofs of fires having lately illumined their 
dark gloom. ‘The great valley, terminating in the horizon’s 
brink, feeding for many miles no stream of magnitude, clothed 
with alternate fields of vines *, maize, and olives, presents all 
the characters of a plain ; while, on both sides, the chains, pre- 
senting a bare perpendicular acclivity, descend into the vale 
beneath (a fact long ago generalised by Bougues), or rear 
aloft their bare for eheads in aged majesty. Goats are here 
the companions of the raven or the eagle; while oftentimes 
the bay of the shepherd’s dog, disturbing the wolf from his 
brake, is heard in the distant mountains, at whose foot man 
appears a rightly diminutive thing. 
Mountains which have not an abrupt acclivity towards the 
valley which they border seldom present a uniform slope 
from their base to their summit, being generally interrupted 
by plateaux or escarpments, which sometimes correspond with 
those of an opposite side. 
The transition rocks, tame in their outline near the limits 
of the chain, become more and more bold as they approach 
the central districts, where they cannot be distinguished in 
their external aspect from the recks constituting the remain- 
der of the crest. In the disposition of the granitic blocks, 
vertically placed on almost all the peaks formed of that moun- 
* It is the vale that furnishes the greater part of the excellent Roussillon 
Ww ime, 
