( 845 ) 
min. to maa. months ~ years 
EBO7SLOTOR Dd ial AL orn nn 3.4 
1878—1883 ..... COC es AD 
1889—1894 ..... EREN 4.4 
1901—1906 ..... Bles ders. 5.2 
The uncertainty in these values is small for the two first periods, 
but considerable for the third, because Dee. ’58 and Feb. ’90 can be 
equally well taken as the real epoch of the minimum *). We have 
adopted the mean of the two. As to the last maximum: Prof. WorrFer 
does not as yet venture to fix its epoch definitively, but it appears 
from already existing data?) that it cannot be earlier than 1906.7. 
It may easily turn out to be still more retarded by half a year. 
The value 5.2 which I assume for @—m must be a minimum, 
therefore *). 
If, in Lockyrr’s diagram, we draw the latest part of this curve, 
it appears to be in contradiction with what was expected by L. 
Instead of falling steeply it still rises. In my figure | have traced 
1) A. Wotrer, |. c. vol. XCIII (1902) p. 90 sq: 
2) A. Worrer, XCIX (1908) p. 288. 
Though the author thus anticipates on the results of a still unfinished inves- 
tigation, he ventures to make the following remarks. 
According to Worrer the present eleven-year period of the sun most clearly 
resembles that of 1823—34. 
The agreement of the highest elevations of the curve is indeed very striking. 
But we may also compare it to the period 1810—23, which is only still some- 
what lower (perhaps as a consequence of incomplete observations) but which 
in its general form, and with its more advanced centre of gravity, still more 
closely resembles the present period If we have to do with a real periodicity, and 
I assume that this is the case, then it will be interesting to ascertain whether 
the next period (1911—1922 norm.) runs in the same way as the flattened one 
of 1823—33. About the year 1913 such must be sensible already in the course 
of the ascending line (the very low values near the minimum too will furnish 
an indication). 
Such indications may prove to be also of importance for terrestrial phenomena. 
After the maximum we must expect very low winter-temperatures, as in 1830 and 1740, 
5) It is true that Epstein (Astr. Nachr. 4237 p. 205) finds a gradual diminution 
from the latter half of the year 1905 to the beginning of 1908, but, on account 
of their inferior conipleteness, his observations have little weight as compared to 
Wotrer’s series. lor the rest, what is particularly important is the “table-form” 
of the smoothed curve 1905—O8 as opposed to the summit-form of the curves 
near 1837 and 1870. 
This strong retardation of the observed phase relatively to the computed phase 
(Newcoms, Aph. Journal XIII, 1901, p. 1) was foreseen for the end of a 
89-year oscillation of the solar activily. See: Proceed. Amst. 27 May 1905, especially 
the table of p. 159, in connection with p. 371 and diagram Ill. These Proc, 
Noy. 1904. 
