as the disc was tilted, however slightly, an action was immediately produced on the receiver.
Fig. 21. The paper disc. AB, CD are the vertical and horizontal diameters.
The disc was now mounted on a stand, between the two screens. By means of sliding arrangements the disc could be raised or lowered, or moved laterally.
In the next experiment, the centre of the disc was first adjusted on the axis, and the disc moved vertically up and down. No effect was produced when this was being done.
The centre of the axis was again adjusted on the axis, and the disc moved laterally on the horizontal slide. In this case, too, there was no action.
By adjusting the vertical sliding rod the centre of
Fig. 22. The holder of the disc. D, the paper disc. V, L are the vertical and horizontal slides.
