Source of currents between electrodes in active nitrogen.—Glowing active nitrogen from an electrodeless discharge tube was drawn in succession through two sets of coaxial cylindrical electrodes. The current between the electrodes of the second set was found to remain constant when the potential betwen the electrodes of the first set was varied from 0 to 250 volts. This indicates that the conductivity is not due to ions drawn from the discharge chamber. By varying the ratio of the areas of the second set of electrodes it was established that the saturation currents were proportional to the area of the negative electrode. It is concluded that the current between electrodes in active nitrogen is due to electrons emitted from the surfaces of the electrodes either photoelectrically or by direct action of the active nitrogen on the metal. The form of the current-potential curves indicates that the electrons are emitted with relatively high velocities.

Effect of He, ${\mathbf{N}}_2$, ${\mathbf{H}}_2$, ${\mathbf{O}}_2$ on the duration of the afterglow.—Helium did not affect the afterglow up to pressures ten times that of the nitrogen. The other gases shortened the afterglow in the order named.

Ionization of foreign gases by active nitrogen.—It was found that active nitrogen did not ionize hydrogen or mercury vapor. Indication of ionization of iodine vapor were obtained. This suggests that the molecule of active nitrogen is ${\mathrm{N}}_2$ in a metastable state with energy between 9.4 and 10.4 volts.

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