If the theory of Prof. Liveing were correct, a coloured line would appear at each border of a disc with broad bands, while the central part would remain uncoloured. However, Prof. Liveing's theory would predict a uniformly coloured band. An experiment was conducted using a disc with a black half and a white half, with three black circular bands of about one centimetre in width. The outer band rotated in the opposite direction to the inner bands. At slow rotation, the inner bands were bordered by bright red lines fading into a dark, reddish ground, while the outer band was black with a brilliant coloured band on its borders. When the direction of rotation was reversed, the results were reversed. The experiment did not prove that the effect was due to irradiation, as the heightened effect at the border could be due to contrast with the surrounding white field. Further experiments on the effect of rotation speed showed that colours changed with speed, contradicting the irradiation theory. When the speed was increased, the colours changed from red to green to blue, and when the speed was decreased, the colours reversed. These changes suggested that the colours were not due to a fixed percentage of vibrations being cut off, as the theory of Prof. Liveing also failed to explain the results. Another experiment with a disc having white lines on a black background showed different colours, indicating that the presence of white or black in the background affected the colours observed. Throughout the experiments, efforts were made to eliminate psychological errors by testing on unacquainted individuals. The results suggested that the colours were not due to a fixed number of degrees of freedom, but rather to the distribution of electrons in different positions of equilibrium. The existence of the "electron" was believed to imply a very restricted number of variables.If the theory of Prof. Liveing were correct, a coloured line would appear at each border of a disc with broad bands, while the central part would remain uncoloured. However, Prof. Liveing's theory would predict a uniformly coloured band. An experiment was conducted using a disc with a black half and a white half, with three black circular bands of about one centimetre in width. The outer band rotated in the opposite direction to the inner bands. At slow rotation, the inner bands were bordered by bright red lines fading into a dark, reddish ground, while the outer band was black with a brilliant coloured band on its borders. When the direction of rotation was reversed, the results were reversed. The experiment did not prove that the effect was due to irradiation, as the heightened effect at the border could be due to contrast with the surrounding white field. Further experiments on the effect of rotation speed showed that colours changed with speed, contradicting the irradiation theory. When the speed was increased, the colours changed from red to green to blue, and when the speed was decreased, the colours reversed. These changes suggested that the colours were not due to a fixed percentage of vibrations being cut off, as the theory of Prof. Liveing also failed to explain the results. Another experiment with a disc having white lines on a black background showed different colours, indicating that the presence of white or black in the background affected the colours observed. Throughout the experiments, efforts were made to eliminate psychological errors by testing on unacquainted individuals. The results suggested that the colours were not due to a fixed number of degrees of freedom, but rather to the distribution of electrons in different positions of equilibrium. The existence of the "electron" was believed to imply a very restricted number of variables.