( ^72 ) 



an txpprecialtle effect on the tola! of this iiiteival. The totals of the 

 eA'ceptioiuilhj severe winters alone are: 7, ii, 6, 2, 10, 6, 3, 0. — 

 In order to keep the division according to whole years T have dropped 

 OJic year — the year 15(i() — near a niininiinn of the period. The 

 last interval of the last period being of conrse unknown, I have 

 taken for this interval the mean of the last column, viz: i, but 

 even a much higher coefficient would not appreciably alter the 

 general results. 



The division of the period can certaiidy not be coutinued beyond 

 a period of 4 X 11-13 years. In our material there is no indication 

 of a regular alternatio]i (at least not in the majority of the cases) 

 of cold and mild })eriods of 22 years. There is even less evidence of 

 a regularity in the succession of the 11-year-periods. 



Taking a period of 44\/.^ years as a basis, we can exjn'ess our 

 results as follows: 



There exist oscillations of c 1 i m ate wit h a j) e r i (ul - 

 i c i t V of 44 ^/^ years and ui u 1 1 i p 1 c s thereof, c h i e f 1 y 

 thus, that one period of 11.13 years contains less 

 cold than the three preceding and 1 h (^ three following 

 ones; that at intervals of 89 years there is one i)eriod 

 with very little cold; that in two cojisecutive inter- 

 vals of J 78 years the last 5 or G periods of one of 

 t h e m a r e col d e r t h a n the c o r r e s p o n ding j) e r i o d s o f 

 the other interval. This oscillation of c 1 i mat e corre- 

 sponds to an oscillation in the "solar activity", of 

 a hiiiher order than the well kjiowu eleven-vear 

 period. 



The very doubtful diiference between two consecutive 178-year 

 periods, which was indicated above, would be in this sense that the 

 greatest amplitude of the oscillations i]i one period occurs in the 

 beginning of the period, and is displaced in the next towards the 

 middle of the first 89-year sub-period. Nothing however can be 

 ascertained on this point, and still less on the existence of still longer 

 periods. 



It seemed interesting to investigate wdiether the 11-year variation 

 of the solar activity itself is shown by this material. For this 

 purpose the distribution of the "cold-coefTicients" over five phases 

 of the eleven-year sunspot period was investigated, r/c. : /j? = 2 years 

 on both sides of the observed minimum, .1/"= 2 years on both sides 

 of the maximum, ap = ascending phase, (Ji\ and dj)., ^= two halves 

 of the decreasing phase. The observed maxima and minima are 

 taken in accordance with Newcomb (the deviations from R. Wolf's last 



