Postcard
Windows MD5 Sum generator.

From: Needham Massachusetts USA

Blurb:

MONOCHROMATIC LIGHT DEMONSTRATION
Museum of Science Boston Massachusetts
The view on the left side demonstrates monochromatic (one colour) light. Only one colour is visible and all that you will ever see is different shades of the colour. This monochromatic light was created through the use of a solium vapor lamp thus creating only yellow light. The other view is seen under normal white light which contains all the colours of the rainbow. Our sun produces white light which allows us to see a great variety of colours - not only different shades of one colour.