On the laws governing electric discharges in gases at low pressures

The experiments described in this paper were undertaken with the object of determining the potential difference required to produce discharge in a number of gases over a wide range of pressures, and especially of ascertaining if the law enunciated by Paschen was generally applicable, provided the electric field in which the discharge took place was uniform. The paper is divided into the following sections :— (1.) Introduction. (2.) Description of apparatus. (3.) Experiments in air. (4.) Experiments in hydrogen. (5.) Experiments in carbon dioxide. (6.) Spark potentials with different electrodes. (7.) Minimum spark potentials. (8.) Connection between spark lengths and spark potentials. (9.) Minimum spark potentials in different gases. (10.) Summary of results.