Alan, Mineral oil has been used also…much easier to obtain. R/Jay From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Alan James Thanks Jay, I was going to jump in the dirty little harbour at the end of the street tonight to try out my lighting theories. I hadn't thought of compensating light fittings with oil, I was going to pot them; however compensating would be much easier & I could use the standard lens on an item I'm looking at. I'm pressuming silicone would be the most suitable oil because of its clarity. Alan |