The traveller who ventures across this arid region has not only to encounter the breath of the simoom, the sufferings of burning thirst, the attacks of wild beasts, the bite of the matacabello--which may kill his steed and leave him helpless--and many other dangers, but, more fearful than all, flames caused by some camp-fire incautiously left burning, seizing the parched vegetation, traverse the plain with inconceivable rapidity. He and his Indian guides, without whom he could not venture across it, discover far-away on the horizon columns of smoke ascending to the skies. The Indians, standing up in their stirrups, gaze at it anxiously for a moment to watch its direction, and then pressing their steeds to their utmost speed, urge him to fly for life. At first he can scarcely believe that yon distant line of smoke is menacing them with danger; but soon onwards it comes, the burning torrent rolling rapidly towards them. Now and then they turn their heads to watch its progress. In vain they look out in every direction for a darker patch in the plain, which may indicate a water pool, and amid which they may seek refuge. None appears. On they rush, urging their horses by whip and spur--their steeds seeming to know their danger. Already they see the bright glare of the flames below the dark mass of smoke. Already the bursting and crackling of the leaves, as the threatening column rushes on, reaches their ears. A fearful death is following them. At length the sharp eyes of one of the guides discover a slight eminence; towards this, though almost despairing of safety, they direct their course. They reach its base. It is but thinly covered with vegetation. Scarcely have they urged up their panting horses to the summit than the flames overtake them. And now the sea of fire rolls its devouring billows around, and the suffocating smoke, striking in their faces, compels them to fall on the ground, in the hope of obtaining sufficient air for breathing, till the flames have passed by. The fire mounts the hill, but happily, finding little nourishment, is speedily extinguished. And now the waving mass, rolling onwards, recedes further and further from their gaze. Whole swarms of voracious vultures follow in circling flight the smoky column, like so many hungry jackals, and pounce upon the snakes and lizards which the blaze has stifled and half calcined in its murderous embrace. Then, with the rapidity of lightning, they dart on their prey and disappear in the clouds of smoke, as if they were voluntarily devoting themselves to a fiery death. Soon the deafening noise of the conflagration ceases, and the dense black clouds in the distance are the only signs that the flames are still proceeding on their devastating path over the wide waste of the savannah.