begins to
produce an effect on coast horses which have not been accustomed to
travel in the Sierra. They are attacked with a malady called the _veta_,
which shows itself by difficulty of breathing and trembling. The animals
are frequently so overpowered that they are unable either to move or
stand, and if they are not immediately unsaddled and allowed to rest
they perish. The arrieros consider bleeding a cure for this malady. They
sometimes slit the horse's nostrils, a remedy which is probably
efficacious, as it enables the animal to inhale the air freely. Chopped
garlic put into the nostrils is supposed to be a preventive of the veta.
Mules are less liable to the malady probably because they ascend the
acclivities more slowly than horses. The disease does not attack the
native horses of the Sierra, for which reason they are better than the
coast horses for mountain travelling. Mules, however, are preferable to
either. It is wonderful with what tact and penetration the mule chooses
his footing. When he doubts the firmness of the ground he passes his
muzzle over it, or turns up the loose parts with his hoof before he
ventures to step forward. When he finds himself getting into soft and
marshy ground he stands stock still, and refuses to obey either stirrup
or whip. If by accident he sinks into a morass, he makes a halt, and
waits very contentedly until he receives assistance. But in spite of all
this sagacity the traveller will not do well to resign himself wholly to
the guidance of his mule. In ordinary cases these animals allow
themselves to be guided, and sometimes they appear to think it more safe
to trust to the bridle than to themselves. One of my mules frequently
gave me curious proofs of this sort of calculation. When, in very
difficult parts of the road, I dismounted, in order to walk and lead him
by the bridle, I found it impossible to get the animal to move either by
force or persuasion. He spread out his legs, fixed his hoofs firmly into
the ground, and obstinately resisted all my endeavors to make him move.
But as soon as I remounted he willingly obeyed every movement of the
bridle. With this mule I could ride through marshes, which I could never
do with any other. He appeared to reflect that, as I only dismounted
when the road was unsafe, his life was in no less danger than mine.

About a league beyond Acchahuari the valley is bounded by the
principal chain of the Cordillera. The ascent may be gained by two