ficulty. The possibility of the vehicle itself moving
occurred to us; but, as I pointed out, the task of replacing their heavy
apparatus in it, and then reassembling the apparatus in a new position,
made such a step impractical.

The only weapon the Mercutians had displayed so far was the light-ray in
its several forms. This seemed effective for ten miles at most. That the
Mercutians could be attacked by our artillery and destroyed seemed
certain.

By the 20th General Price had mobilized some ten thousand men. They
encamped on the prairie near Billings. The artillery was moved down to a
point near the Wyoming State line, about fifteen miles directly north of
the Mercutian camp.

Six days before this, forty-eight hours after I had returned to Billings,
observation planes had reported the establishment of two more light-rays,
similar in appearance to the first. During the succeeding days others
rapidly appeared. By the 20th there were probably thirty of them
altogether.

The reports stated that all were set up within a space seemingly of a few
hundred yards. They were of different diameters; some projected in
parallel rays, others spread out fan-shaped. These latter appeared not to
carry so far. The first one that had appeared, it was judged, had the
longest effective radius of them all.

During these days and nights preceding the 20th the light-rockets had been
fired with increasing frequency, but none was observed to carry over six
or eight miles. By this time the burned area for a circle of ten miles all
around the Mercutian camp was entirely depopulated, and no additional
destruction was reported.

On the night of the 20th, firing by directions from captive balloons, the
United States artillery began its bombardment from the Montana-Wyoming
line. After sending over some twenty shells, the firing ceased. It was
learned then that they had proven utterly ineffective. The diverging rays
of the Mercutian light had thrown a barrage around their position. The
shells striking the light had all exploded harmlessly in the air.

Subsequent bombardments made that night met with no better success. The
fact became obvious then that to artillery fire the Mercutians were
impregnable. For several days no further military operations were
attempted, with the exception of an occasional shell futilely thrown
against the light-rays.

The newspapers during these days were full of discussions--scientific and
otherwise--as to how th