There was no one on the stairs; evidently every one living in the castle was now on its roof--some thirty of them altogether. The crowd outside quite evidently had no present intention of entering the building. The mob of peons Baar had gathered were greatly in the minority now, and I felt that matters were steadily improving. I wondered where Miela was, and then while I was standing there I saw her coming up the stairs, a man following close behind her. I think I have never been so glad to see any one as I was to see her at this moment. Her face was grave; her demeanor calm, as before. "He is here," she said as she came to the head of the stairs. "This is Fuero, Alan, leader of the men of science, who have the ray." As he came out onto the roof I saw this man was easily the most dominant personality I had so far encountered on Mercury. He was tall for his race, although several inches shorter than I, a man of sixty, perhaps, with iron-gray hair falling long about his ears. He wore sandals and a pair of the usual knee-length, wide-cut trousers. But what distinguished him in his dress was a broad panel of heavy silk, hanging from neck to knee, both in back and front, with an opening at the top through which his head was thrust. This silken panel was some eighteen inches wide, light gray in color, and richly embroidered in gold in various designs. It hung free, except for a slight fastening at the waist line. Beneath it the man's naked torso--and his bare arms--showed powerfully muscled. His face was smooth shaven, with strong, regular features. I noticed, too, there was a slight cleft in his square chin. His forehead was high, his blue eyes kindly, yet with a searching, piercing quality about them. It was not so much the man's general appearance as his bearing that made me realize he was a forceful character. There was about him unmistakable poise. I knew at once he felt his power, his authority. That he would use it wisely I could not doubt. He stood regarding me gravely--an appraising regard under which I felt myself flushing a little. Miela spoke to him swiftly, and he inclined his head to me by way of introduction, his glance meanwhile taking in the scene on the roof. With Miela as interpreter we held a hurried conversation. I learned then that Fuero and his associates had many years before organized a society for the development of the light-ray in its various forms. They had soon realized in their experiments its diabolical power of destruction, and had taken oath then that they would not use it, or allow it to be used, except under the most critical circumstances of the nation's welfare.