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 this strange enemy of mankind could be destroyed or dislodged. This was like no other warfare in history. The newspaper statements gave the inference that General Price was entirely at a loss how to proceed. As a matter of fact, the press was quite correct in that assumption; and, since the Mercutians were making no offensive moves, General Price decided to do nothing until he was better informed. I was fortunate enough to be present the next day at a conference the general had with several scientific men who had come to Billings to meet him. It was the opinion of these men of science that no artillery fire could penetrate the light-barrage the Mercutians had thrown about them. No airplane attack was practical, and to attack them from the ground with infantry would be absurd.