found for oil drops has been inserted,
, which is in better agreement with the result obtained with oil drops than we had any right to expect. In these experiments the light was weak so that the changes come only after an average interval of 29 seconds and it will be seen that they are all unit changes.
[Table XIII]
MERCURY DROPLET OF RADIUS
DISCHARGING
ELECTRONS UNDER THE INFLUENCE OF ULTRA-VIOLET LIGHT
| Volts | Drop No. 1 Sec. per Cm. | Sec. per Cm. | Time Interval between Discharges in Seconds | Charge in | No. Electrons Emitted | |
|---|---|---|---|---|---|---|
| 2.260 | 11.0 | - 1200} | {49.4} | |||
| 3.070 | 11.0 | + 32.8} | {50.5} | |||
| 11 | 4.4 | 1 | ||||
| 1.960 | + 194 | 54.4 | ||||
| 12.8 | ||||||
| 1.960 | + 190 | 60.8 | 6.4 | 1 | ||
| 23 | ||||||
| 1.820 | 11.2 | + 220 | 65.0 | 4.2 | 1 | |
| 40.0 | ||||||
| 1.690 | + 230 | 69.8 | 4.8 | 1 | ||
| 15.2 | ||||||
| 1.550 | + 332 | 75.1 | 5.3 | 1 | ||
| 3.040 | Drop No. 2 10.4 | + 98 | 43.5 | |||
| 5.6 | ||||||
| 2.540 | + 200 | 49.4 | 5.9 | 1 | ||
| 18.6 | ||||||
| 2.230 | + 300 | 55.2 | 5.8 | 1 | ||
| 35.0 | ||||||
| 2.230 | + 76 | 60.7 | 5.5 | 1 | ||
| 42.0 | ||||||
| 1.930 | + 200 | 65.0 | 4.3 | 1 | ||
| 54 | ||||||
| 1.810 | + 176 | 69.6 | 4.6 | 1 | ||
| 70 | ||||||
| 1.650 | + 250 | 75.2 | 5.6 | 1 | ||
| 45 | ||||||
| 1.520 | + 500 | 79.4 | 4.2 | 1 | ||
| 9.8 | ||||||
| 1.520 | + 119 | 85.1 | 5.5 | 1 | ||
| Mean | 29 | Mean | 5.1 |
So long, then, as we are considering the ionization of neutral atoms through the absorption of an ether wave of any kind, the evidence at present available indicates that the act always consists in the detachment from the atom of one single negative electron, the energy with which this electron is ejected from the atom depending, as we shall see in [chap. X], in a very definite and simple way upon the frequency of the ether wave which ejects it.
IV. IONIZATION BY