the considerable falling off for mediocrity when only the first degree of relationship is considered, but it will be seen that the falling off is relatively greater when we consider the eminent relations of mediocrities than when we regard the eminent relations of geniuses.
In the second degree of relationship the average of the 9, 10 have about 1.7 eminent relations while the mediocrities have about .6. In the first degree the average of the 9, 10 have about .85 eminent relations while the mediocrities have but about 2.. In other words, in
the second degree the geniuses have about 2.83 times as many relations in the genius grades as the mediocrities have, while in the first degree they have about 4.25 or the regression from the first to the second degree is .6659. This is strikingly close to Galton's first estimate for filial and fraternal regression given in 'Natural Inheritance,' p. 133, as 2⁄3.
With regard to the relationship between genius and insanity, it is to be observed that the line does not fall off as we go from the mediocre
