Thanks. I'll try those other tools. I've been hearing from other people I should probably do my modeling with other tools. But if this can be done in Bryce, I'd love to understand how. As you can see from my Web site, I have been using the terrain editor to build the dirigible hull one rib at a time. I'm not happy with this because I don't have a lot of control over the bitmap I'm using (how to paint a nice gradated range of tones representing the curve of the hull?) and in any case this method, while it looks cool, results in a dirigible comprised of at least 72 objects, which is too many just for the hull. Makes scene files unwieldy. A symmetrical matrix won't help me until I can figure out how to produce a greyscale bitmap to describe the hull. If you know how to make some very nice dirigibles in Bryce, I'd love to hear more. Thanks, Mitch http://www.employees.org/~redneck/graphics/journal_01.htm