La gran astada ––por tal se le conocerá probablemente el guarda o vigía de un rebaño invisible al cazador; mas por fortuna estaba mirando en dirección opuesta a éste y no había advertido su presencia.
The big-horn—for so it is called—was acting, probably, as a guardian over a flock which were invisible to the hunter; but fortunately it was heading in the opposite direction, and had not perceived him.