Absurdly simple, the dreamachine creates a flickering of light calibrated to match alpha brainwaves. It is this that induces the multiplicity of colour and image in the brain. Gysin based his device (designed in collaboration with Ian Somerville) on the work of W. Grey Walter, one of the pioneers of the mechanics of brain function. The booklet contained just a couple of short essays, plus a card template and instructions on how to build your own dreamachine. Apart from a sheet of card, all that was needed was an old 78rpm record deck, and a light bulb. The dreamachine crosses the line between art and experience, and is the first device designed to be viewed with eyes closed.