Positive wire only attached.
(b) The positive wire only was attached to one electrode, the negative being unconnected. A set of faint whity-blue cobweb-looking streams of light spread from the electrode all over the receiver, having a vibratory motion. The spaces between these were dark, and there was no aura—the effect being similar, but not quite so bright and pronounced, as when both wires were attached (see Plate XVIII. fig. 7).
Negative wire only attached.
(c) The negative wire only was attached. The cobweb streams were absent, or only shot out very occasionally. The main effect was a straight nebulous stream of violet light, which commenced at the electrode and spread out in a fan-shape towards the lower brass cap of the receiver; while, at the same time, an aura or glow of similar light, but fainter in quality, spread from the electrode over at least one half of the receiver. This aura would no doubt have filled a small flask (see Plate XVIII. fig. 8).
Effect of gradual exhaustion on the discharge.
(d) When exhaustion was first commenced, both electrodes of the receiver (both wires being connected) threw out spider-web-like streams, as in Experiment 1, pale blue from the one pole and somewhat rosy from the other.
As the exhaustion progressed the pale-blue streams disappeared, while the rosy flickering ones diminished in quantity and extent until ultimately a single rosy stream of light crossed the receiver as in Experiment 5a. Upon admitting the air, these effects took place in an inverse order—the single stream being gradually broken up, and the spider-webs taking its place.
Globular receiver placed on poles of the magnet. Magnet effect.
(e) The exhausted globular receiver was placed upon the poles of the excited magnet, with the stream at right angles to them. Looking across the S. pole of the magnet, the negative electrode was on the left hand, and the positive on the right. The effect of the magnet on the stream was apparently to split it up into several; but this appearance must have been due to vibration only, as a revolving mirror showed the stream as single. When the current was reversed, the stream which, without the magnet, was somewhat flickering and vibrating, slightly straightened at the positive pole, and the whole stream became steadier.
Single wires attached.