downcast upon the trail, the hindmost man watched the haze that
crept down the vastness of the valley, nearer and nearer, and noted
how the wind grew in strength moment by moment. Far away on the left
he saw a line of dark bulks--wild hog perhaps, galloping down
the valley, but of that he said nothing, nor did he remark again upon
the uneasiness of the horses.

And then he saw first one and then a second great white ball,
a great shining white ball like a gigantic head of thistle-down,
that drove before the wind athwart the path. These balls soared
high in the air, and dropped and rose again and caught for a moment,
and hurried on and passed, but at the sight of them the restlessness
of the horses increased.

Then presently he saw that more of these drifting globes--and then
soon very many more--were hurrying towards him down the valley.

They became aware of a squealing. Athwart the path a huge boar rushed,
turning his head but for one instant to glance at them, and then
hurling on down the valley again. And at that, all three stopped
and sat in their saddles, staring into the thickening haze that
was coming upon them.

"If it were not for this thistle-down--" began the leader.

But now a big globe came drifting past within a score of yards
of them. It was really not an even sphere at all, but a vast, soft,
ragged, filmy thing, a sheet gathered by the corners, an aerial
jelly-fish, as it were, but rolling over and over as it advanced,
and trailing long, cobwebby threads and streamers that floated