84 Proceedings of Indiana Acadejmy of Science 



Summary and Conclusions. 



1. The sparking potential between points in fresh nitrogen is 

 roughly 60 per cent of that value for oxygen under the same conditions. 



2. If nitrogen has been subjected to heavy sparking its sparking 

 potential is reduced and remains so for some time. 



3. The presence of a metal plate midway between the electrodes 

 increases the sparking potential in nitrogen from 30 to 60 per cent 

 but has no appreciable effect in the case of oxygen. 



4. The sparking potential with a 5 mm. hole in the metal plate 

 is only slightly greater than that of the gap alone. 



5. If a metal plate is placed midway between points discharging 

 in nitrogen, it acquires, at low potentials, a strong negative charge, 

 but if the voltage is increased sufficiently, the sign of the charge is 

 reversed. If the discharge takes place in oxygen the negative charge 

 acquired by the plate is very much less than for nitrogen, but con- 

 tinues to increase up to the sparking potential. 



6. The effect of time of discharge at constant potential, on an en- 

 closed volume of nitrogen, is to cause a reduction in the initial negative 

 charge on the plate, which under certain conditions may change sign 

 and become positive. 



7. Oxygen is consistent in its behavior under the influence of the 

 discharge. 



8. The discharge in nitrogen takes a number of forms depending 

 upon potential, previous history of the gas, time of discharge and ma- 

 terial placed in the path of the discharge. This indicates the foi'mation 

 of an activated nitrogen whose electrical properties are greatly different 

 from those of the unaffected gas. 



9. Measurement of the charge acquired by a metal plate placed 

 between needles discharging in nitrogen might possibly be used to deter- 

 mine when nitrogen is in the proper state to unite with other elements. 



A more complete account of this work together with much other 

 material will be found in an Engineering Experiment Station Bulletin 

 to be published in the near future. 



The gas used in these experiments was kindly donated by the Cleve- 

 land Wire Division of the National Lamp Works through the courtesy 

 of Mr. B. L. Benbow. 



