ANALYSIS OF TERRESTRIAL RECORDS 



101 



occurs three to five or more times in succession and the cycles seem to merge 

 as they change and the chances are greatly against accident. As the length 

 of the fraction increases, for example, from 4| to 1\ years, accident becomes 

 less and less likely. So even three curves in succession showing three sub- 



A.D. 

 1213-1327 



2 4 6 8 10 12 14 16 18 20 2223 

 Fig. 43 — Scrambled sequoia values tested by "triple lag" method. 



divisions are very probably real. We find, for example, a Hellmann cycle 

 lasting from about 1760 to 1910 or so, an interval of 150 years containing 

 more than 25 repetitions, as appears in figure 44. It does not disappear 

 during the changes in the sunspot cycle near 1800. 



