The canter up was brisk, and after giving our horses the drink from
the running stream they always beg for, we started back on the road to
the post in unusually fine spirits. Almost immediately, however,
Lieutenant Baldwin said, "I do not like the looks of that cloud over
there!" We glanced back in the direction he pointed, and seeing only a
streak of dark gray low on the horizon, Lieutenant Alden and I paid no
more attention to it. But Lieutenant Baldwin was very silent, and ever
looking back at the queer gray cloud. Once I looked at it, too, and
was amazed at the wonderfully fast way it had spread out, but just
then John shied at something, and in managing the horse I forgot the
cloud.

When about two miles from the post, Lieutenant Baldwin, who had fallen
back a little, called to us, "Put your horses to their best pace--a
sand storm is coming!" Then we knew there was a possibility of much
danger, for Lieutenant Baldwin is known to be a keen observer, and our
confidence in his judgment was great, so, without once looking back to
see what was coming after us, Lieutenant Alden and I started our
horses on a full run.

Well, that cloud increased in size with a rapidity you could never
imagine, and soon the sun was obscured as if by an eclipse. It became
darker and darker, and by the time we got opposite the post trader's
there could be heard a loud, continuous roar, resembling that of a
heavy waterfall.

Just then Lieutenant Baldwin grasped my bridle rein on the right and
told Lieutenant Alden to ride close on my left, which was done not a
second too soon, for as we reached the officers' line the storm struck
us, and with such force that I was almost swept from my saddle. The