NO, 2 WASHINGTON PRECIPITATION OF I954 AND I955 — ABBOT 3 



I give in table 2 the 175 dates when higher average precipitation 

 may be expected in 1955 than the average precipitation of all other 

 dates of 1955. The first column, in Roman figures, gives the "pre- 

 ferred" days of the 27.0074-day cycle. The remaining columns give 

 the actual dates in the 12 months of 1955 when these "preferred" 

 cycle dates recur, and when higher than average daily precipitation in 

 Washington may be expected, taking the year as a whole. 



The basic tabulation, on which the table rests, began with January i, 

 1924, and ended with December 1941. There has been no apparent 

 divergence from this cycle in recent years, except in 1952 and 1953, 

 and it appears to be satisfactory as a basis for 1954, and is used here 

 for 1955. So the decimal 0.0074 seems correct for over 30 years. 

 This cycle corresponds closely with the average period of rotation of 

 the sun, and was suggested by a corresponding period in the Smith- 

 sonian measures of the solar constant of radiation. The cycle is more 

 strongly marked in these measures in some years than in others. 



