10 Generating Economic Cycles 



computed its maxima are, within the limits of the 

 errors of observation, coincident with the maxima 

 of the eight-year rainfall cycle in the Ohio Valley, 

 which, in 1914, was found to have persisted 

 throughout nine consecutive periods; 

 (3) The amplitude of the eight-year cycle in the 

 United States is relatively so large that it ac- 

 counts for 42 per cent of the total variabiUty of 

 the annual rainfall. This result is obtained by 

 taking the ratio of the amplitude of the eight- 

 year cycle to the mean of the annual rainfall 

 departures irrespective of their signs. 



These meteorological facts raise important questions 

 in the extremes of the hierarchy of the sciences. If the 

 regularities that have been observed are not accidental 

 they are probably cosmical in origin, and one of the 

 leading questions they suggest relates to the astronomic 

 and physical agents by means of which they may be 

 produced. The fourth and fifth of the following chap- 

 ters enter into the details of this question. 



While solar physics must be looked to for an explana- 

 tion of the weather regularities, the regularities them- 

 selves are the starting point of the economist's inquiry 

 into cyclical economic changes. He wishes to know 

 whether the observed cyclical recurrence of rainfall 

 with its large amplitude may not originate agricultural 

 cycles which, in turn, generate the cycles of production 

 and the cycles of prices mth which the economist is 

 more immediately concerned. The second, third, and 

 fourth of the ensuing chapters treat of the details of this 

 economic problem. 



