The purpose, as I am sure you are aware, is to increase the thrust of the vessels in combat conditions, so that they might better outmaneuver their attackers. All my efforts to readapt a single crystal failed. The conversion is a function of the crystal's composition, its shaping and its placement in the parse tube. A single crystal has a finite capability for conversion of light into energy, and there is nothing I have found that will alter that.»

  He nodded, as if to reassure himself that he was right about this. «So I abandoned that approach and began to experiment with multiple crystals. You see, Prime Minister, I reasoned that if one crystal will produce a certain amount of energy, then two working together might double that figure. The trick, of course, is in finding how to channel the ambient light from one crystal to the next without losing power.»

  Sen Dunsidan nodded, suddenly interested. He thought he understood now why Etan Orek had been so anxious to bring him there. Somehow, the engineer had solved the dilemma that had plagued the Federation for years. He had found a way to increase the power generated by the diapson crystals used in his airships.

  «At first," the other went on, «all of my attempts failed. The crystals, when I found a way to place them so that their facets transferred their converted energy from one to the other, simply exploded in the tubes. The additional power was too much for any one of them to handle. So then I began working to combine more than two, attempting to find a different way to channel their energy in a manner that was not so direct and less likely to incur damage.»

  «You were successful?» Sen Dunsidan could not contain himself. Etan Orek's insistence on dragging out this business was wearing on him. «You found a way to increase the amount of thrust?»

  The little man shook his head and smiled. «I found something else. Something better.»