( 206 ) 
May + 17 Sept. — 2 Jan. + 9 - 
June — 2 Oct. — 4 Febr. — 8 
July + 6 Nov. + 9 March — 8 
Aug. — 9 Dec. + 1 April — 3 
The fact that the supplementary term can be represented by a 
simple sinusoid and that a half-yearly inequality is not shown, agrees 
with the result found a moment ago, that no term varying as the 
square of the temperature is indicated *). Properly speaking the two 
results are equivalent. 
16. Finally I have again tried to clear the monthly means of the 
rates, as well as possible, of all periodic terms. In doing this I have 
applied no further corrections for the influence of the temperature 
because the variation of its coefficient — the results of the years 
1871 and 1873 are just those differing most considerably — did not 
seem as yet sufficiently demonstrated. 
No other reductions were applied, therefore, but those for the 
supplementary term according to the formula found above. 
The rates corrected in this way (= term a) have been inserted, in 
the table already given, in the column Red. D. R. IL. 
These values of the term a have been represented as well as 
possible by a simple curve reproduced in Fig. 5. 
In this figure the results of the observation are also shown, not 
for every month separately, but for the mean of any three consecu- 
tive months ®). 
I have tried to draw this curve about as simply as that for the 
period 1878—98. The outstanding differences O—C (C = curve) 
are contained in the last column of the table. 
These differences lead to the following mean amounts, which we 
might consider as the mean errors of a monthly mean : 
1862—1867 M. B. =>+ 05.0309 
1868—1874 ‚0273 
1) The remark made at the end of § 7, p. 23 (90) does not make sufficient 
allowance for the fact that, as long as no physical explanation has been given for 
the ‘supplementary term’, a variability of this term might be deemed no more 
probable than the variability in the course of time of a term varying as the square 
of the temperature. 
2) On page 24 (91) I forgot to remark that the same was done in Fig. 3, which 
represents the period 1878—1898, 
