Index of refraction for glass using image depth

Marlinda and Welianter attempt to measure the image depth while Elsieleen looks on.

Below, Charles is working on the apparent depth of a penny. My own preference is to use a flat sheet of paper with printing on it.

To the right of Charles' stack are pieces of tinted window louver. These are too dark to be useful.

This particular laboratory exercise depends on a supply of old window louvers. The complication is that the louvers are usually coated with a coralline layer that is all but impossible to remove. Put away the ammonia based cleaner - those are useless. I was able to restore very old panes to near new transparency using a sulfuric acid based toilet bowl cleaning compound. Use gloves and goggles! The louver above had only the right hand side cleaned.

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