I know that water drops act as a prism to turn white light into the visible spectrum. What I don't understand is how come many prisms are meant to seperate the colours. What I mean is the following. One prism would make red, orange, yellow, green, blue. Two prisms would not make red red, orange orange, yellow yellow, green green, blue blue. It would make red, orange, yellow, green, blue, red, orange, yellow, green, blue. 1 prism: http://homepage.ntlworld.com/ak_gara/Rainbow_1.gif [Broken] 2 prisms: http://homepage.ntlworld.com/ak_gara/Rainbow_2.gif [Broken] Many, many prisms: http://homepage.ntlworld.com/ak_gara/Rainbow_3.gif [Broken] How is the red from all over meant to go to the left, and all the blue from all over go to the right, and all the green all over go to the middle?