Hi Dr. Bob,
Well, it's been raining here in Texas for days. Not too hot but very humid.
With the image, you were right, I just set a constant IOR for the entire solid and the computer did the rest. Here's another one, only this time I made the surface highly reflective and not transparent at all. I'm using a program called POVRay. Check out www.povray.org. It is a "ray-tracing" program. I think that how it basically works is by computing thousands of rays from the camera viewing plane into a scene and letting the rays bounce or bend when they strike surfaces, depending on various definable surface attributes, hence the name "ray-tracing". I think that rays are also computed from light sources. This is the kind of technology that makes the animation in movies like Lord of the Rings.
Chris
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