Purpose: Demonstrate canal rays present in a cathode ray tube.
Description: Perforations in the cathode of the tube permit positive ions to pass through the cathode, forming "canal rays" or "positive rays." The effect of a magnet on these rays may be compared with its effect on electrons moving in the opposite direction as in demonstration K1-12: CATHODE RAY TUBE - DEFLECTION BY MAGNET. The deflections of the beam are visible if viewed closely with very low ambient light level.
