Tim, You sent me an email about using baby oil and colored water for the wave machine, I replied, and said that the specific gravities of the materials would not produce the desired results. I was rethinking your suggestion and came to the conclusion that I was wrong. My logic was reversed. The heavier water would sink below the baby oil, as it should. I am buying some baby oil and will try it. Thanks again for your input. I apologize for my error.
Thanks for the comment on the liquid used in the Simplex Wave machine. I believe it must be something other than Baby oil though, since the specific gravity of mineral oil (baby oil) is .8 compared to water, which is 1.0. This would cause the baby oil to float on top of the water, since it is lighter than water. The blue colored liquid in the Wave, creates waves below the surface of the clear liquid, indicating it is heavier than the liquid above it. If you should find any more information, please send it to me.