An active modification of nitrogen. -VII

In previous papers attention has chiefly been paid to the properties of active nitrogen when produced. The present one deals almost entirely with the circumstances of its production by the electric discharge. The jar discharge is much the most efficient, but does not lend itself easily to quantitative investigation. It is not easily maintained steady for any length of time, but there is a more fundamental difficulty than this, for measurements of current and potential with the jar discharge do not admit of any simple interpretation. Each discharge lasts for a time which is very short compared with the intervals between discharges, and, when it does occur, it is oscillatory. For these reasons attention has been given to the steady discharge obtained from a direct current dynamo machine. This yields much less active nitrogen than the jar discharge, but still enough to admit of satisfactory observations on many points.