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                Water tank The same tank as was used in experiment no.
                    1.  Working Fluid Salt water used to form stratified
                    layers.  Visualization Moiré
                    technique. The room is darkened, the
                    shutter of the camera is left open for a
                    half-period of the wave, and red and blue
                    strobes are lit up a half period apart,
                    making two images on the one film. After
                    developing the film, the positives are read
                    into a computer with a film scanner and the
                    red and blue images are separated to make a
                    Moiré image.  Experimental process The same process as experiment no. 1 was
                    used.  |   |