Invisibility cloak

Years ago I found out that some objects can be made completely invisible. At the time I was working at the stage 2 chemistry lab at the Central Institute of Technology (Heretaunga Campus) in room A402.
After investigating it, I learned that the solution of ferric chloride in the beaker had exactly the same refractive index as the glass rod standing in it. The effect was that the part in the liquid could not be seen at all!
So in case you are interested in this effect, maybe you can re-create it with a little time and care! Note: The approximate date of this experience was 1974/75.
Postscript: A claim was made recently concerning a real life invisibility cloak. If you would like to know more please go to more here