抄録
Different measures of range in use are defined and discussed. Expressions are obtained (a) for correcting the smoothing effects on the various measures of range, and (b) for comparing two measures of range. It is shown how these depend on the time of maximum and therefore to some extent on season. The smoothing corrections when the maximum is at 1100hrs. L. T. vary from 1/2 to 151/2% for measures of range based on averaging over one to 4 hours. The ratio of any two measures of range is found not to be significantly different between H at Huancayo and Z at Ibadan nor between years of solar activity maximum and minimum.
