Return to Dakistee by Thomas DePrima Page B

to the door. She was so startled that she just stared it for some thirty seconds as she tried to reason why it should behave like that. Recovering from her absorption, she reached out and plucked the cylinder from the door, then again held it close to the door, but a meter to the right of the first spot. She watched, fascinated, as it again leapt from her hand and clung to the door.
    "This doesn't make any sense," Christa said. "Dakinium doesn't have magnetic properties, yet it's acting like it does." She plucked the cylinder from the door and carried it over to a Chembrite light where she held it against the steel support stand. There was no magnetic attraction. "Well, the magnetic properties aren't in the cylinder. It must be something in the composition of the door."
    "Did you notice," Carmoody asked, "that it only stuck on circles both times?"
    "Did it? Let's check that out."
    After ten minutes of experimentation, the results seemed conclusive. The cylinder would only stick to the areas inside the six circles, but it stuck equally well inside any of them.
    "So, either there're magnetic properties in the door and the cylinder has a steel core, or the Dakistee ancients discovered some property of Dakinium that we don't yet know," Christa said. "Did you notice the rod always aligned with one of the thirty-eight marks on the circumference?"
    "Yes, I did," Carmoody said.
    "It would seem we have part of our answer," Christa said.
    "We do?" Carmoody said with surprise. "What is it?"
    "The circles must represent a locking mechanism. There could be no other reason for having such an elaborate arrangement on the door. It has to be a combination lock."
    "Okay, but how does it operate?"
    "I can think of several possibilities. You could place the cylinder on a circle, beginning in a certain position, then twist it to a new position. We've already established that it will align in any of thirty-eight directions. But that could be problematic if there wasn't a way to reset the lock since there's no visible indication of where an internal cam is presently pointed, so it's more likely that simply placing a cylinder against the door enables a mechanism. However, that theory relies on there being five more cylinders. So— to open the door, you must have the proper cylinder on the proper circle, aimed in the proper direction. It's incredibly simple and yet incredibly complex at the same time."
    "I'm not following you. It doesn't sound that difficult if you have the cylinders."
    "That's why it seems incredibly simple, but if I'm correct, we must not only have all six cylinders, but we must know the exact position required for each. Each of the required cylinders might have been entrusted to an important individual on the planet and only that individual knew the proper alignment of their cylinder. That makes it both a key lock and a combination lock in one. You must have all the pieces and the knowledge of the combination to open the door. Having only one part won't do it."
    "If that's true," Carmoody said, "there's another possibility. What if one of the circles was meant to be left without a cylinder, although six cylinders were made. It would be like having six deadbolts on a door where you had no information if the bolt was currently open or closed."
    "Yes. If just one of the deadbolts isn't retracted, the door remains locked."
    "I wonder how many permutations are possible? Assuming that all six cylinders are required, what's thirty-eight raised to the sixth?"
    "Roughly three billion, eleven million combinations," Christa said. "However, there's another consideration. I'm assuming that each cylinder has a different 'magnetic' strength value, so you must have the correct cylinder on the proper circle. This raises the possible combinations to eighteen billion." She released a soft sigh and added, "It might take a few days longer to open the door than I had anticipated before my arrival."
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Chapter Five
    ~ May 16 th , 2285