Jefferson wrote: > Andrew Janssen wrote: > > >>Kaeir might find such a system useful; the Islands and Tirmaeir are >>close enough to be linked by such a system. >> >>As a rule of thumb, according to a website about heliographs that I >>found, every inch of mirror diameter gives you ten miles of range. A >>ten-inch mirror would be large enough to signal across the channels >>separating the islands from each other and the mainland. > > > I think you'll find that those mirrors are _parabolic_ mirrors, which Qaiyore > doesn't have the technology to make. I believe flat mirrors give you about > 100 yards per inch diameter under ideal conditions, and the best (less than > flat) mirrors available on Qaiyore would be worse. As far as I am able to determine from the website that I got the information from, the mirrors are flat, rather than parabolic. > Also, taking the world's curvature into account, each of your observers and > mirrors would need to be a minimum of 1380 feet above sea level. Where on earth do you get that figure from? Andrew > Jefferson > http://www.picotech.net/~jeff_wilson63/rpg/Exq_Main.html > > > > ---------------------------------------------------------------- > To unsubscribe, send mail to celandra-off@phoenyx.net. > ---------------------------------------------------------------- To unsubscribe, send mail to celandra-off@phoenyx.net.
