1.—Several investigators have claimed that electrons are emitted from metals under the influence of chemical action, but the only claim which seems well substantiated is that of Haber and Just, who found that when drops of cæsium or of the liquid alloy of sodium and potassium are attacked, at a low pressure, by a number of chemically active gases, the drops lose a negative but not a positive electric charge. The electric currents set up with the drops negatively charged are stopped by the application in a suitable manner of relatively small magnetic fields. This shows that the currents are carried by electrons emitted from the drops. The object of the present investigation has been to obtain quantitative information about this interesting phenomenon, and, more especially, to ascertain the magnitude of the kinetic energy of the emitted electrons and the mode of its distribution among them. The importance of the subject lies in the fact that it is the only way, so far as I am aware, in which any information at all can be made available as to the distribution of energy among the individual products—molecular, atomic, ionic or electronic—of a chemical reaction. The majority of the experiments have been directed towards obtaining the curves showing the relation between the chemical electron current and the applied electromotive force for the case of a small spherical source concentric with a large spherical electrode.
Current collection by an active spherical electrode in an unmagnetized plasma