For two hours I watched them, and then, bored with the monotony of it, returned to the hotel.

After an hour, from beneath my window, I still could hear them; another hour and another went by.

They still were passing.
Boredom gave way to wonder.

The thing fascinated you, against your will, dragged you back to the sidewalk and held you there open-eyed.
No longer was it regiments of men marching, but something uncanny, inhuman, a force of nature like a landslide, a tidal wave, or lava sweeping down a mountain.

It was not of this earth, but mysterious, ghostlike.