the difference in the two eases being that, for the period now under 
discussion, the clock was only enclosed in a single case. 1 will set 
down only the results which I found for the means of the 5 daily 
readings in the years 1873—76. 
u.—l. u.—l. 
Jan. + 0.32 July + 0.44 
Febr. + 0.34 Aug. + 0.40 
March + 0.38 | Sept. + 0.5 
April + 0.42 Oet.” 20:30 
May + O44 Nov. + 0.31 
June + 0.44 Dee. + 0.31 
These differences are corrected for index-errors. 
12. With a few exceptions I used for the time before 1872 the 
same time-determinations from which Kaiser had formed his monthly 
means of the rates. Some corrections however could be applied. 
The clock had been set going in June 1861 but I left out the first 
year and placed the beginning of my investigation at 1862 May, as 
Kaiser had done. It ends April 1874, a short time before the oceur- 
rence of the perturbation. 
The observed rates were first reduced to 760 Mm. at 0° and to 
+ 10° R. For the coefficient 6 I again took + 0:.0140 (Kaiser in 
his last investigation found ++ 0.0134) and for ¢ I adopted the value 
— 0.0174 which is the mean result of Karser’s last investigation, 
allowance being made for the fact that I now reduced the barometer- 
readings to O°. 
In the following table all the columns have the same meaning as 
the corresponding ones in the table for the period 1877—1898. 
