In your sadhana, has anyone ever read about meditating in the light rainbow of a prism?
An interesting fact regarding the light rainbow of a prism, is that there are 7 colors, which maps easily to the chakras.
In the book "A Search in Secret India", Paul Brunton visited many yogis and ashrams. One visit in particular was to an occultist who was doing experiments with concentrated light passing through a prism.
In the book, "Beelzebub's Tales to his Grandson", G.I.Gurdjieff describes an apparatus using prisms.
My idea is to create an environment where you can sit and meditate so that the light rainbow of a prism shines on your body. As the earth rotates, as each rainbow color passes by, you would visualize each chakra in turn, repeating the appropriate mantra, lam, vam, ram, ham, yam, om, etc
Have anyone ever heard of this, what do you think?