Eight-Year Cycle in Relation to Physical Cause 129 



unable to support the theory of a real planetary effect. 

 Only in the case of the 3 h. maximmn for Venus . . . 

 does the mequality continue strongly throughout the 

 series of observations " (p. 14). Resorting to the theory 

 of probability to determine whether this apparent effect 

 of Venus is a real effect, he concluded: "In general 

 practice a de\dation from the mean of less than three 

 times the standard de\'iation is regarded as ascribable 

 to fluctuations of sampling" (p. 14). "The standard 

 deviation for the Venus spot-birth is 9.7. A residual of 

 30 in the figures for 3 h. does, according to the above 

 criterion, call for explanation. Dr. Schuster suggests a 

 planetary effect. To the present writer the evidence 

 seems so uncertain that he prefers to suspend judgment 

 mitil more figures are available " (p. 15). 



The net result, for our purpose, of Mr. Stratton's 

 review of Professor Schuster's work is that he finds the 

 same formal indication of an effect on the part of Venus. 

 Professor Schuster, reasoning from probabilities, re- 

 gards the effect as real while Mr. Stratton, admitting 

 the very great probability in favor of a real effect, 

 prefers to suspend judgment until more figures are avail- 

 able. 



If the Venus effect is real, then there is need of ex- 

 plaining how it is produced. One of the theories ad- 

 vanced by Professor Schuster is that the solar perturba- 

 tion may be due to an electrostatic influence on the 

 part of the planets, and he assumed that the planetary 

 electrostatic influence would hardly diminish more 

 rapidly than according to the inverse third power of the 

 distance from the Sun. 



At this point Professor Schuster's argument respect- 



