WHOLE VOL. NOTES. EUROl'E 55 



111 order to make the series homogeneous these means have heen 

 eorrected to the means of 24 hourly ohservations hy apply- 

 ing the following corrections : 



18.57 1808 1871 1857 ISfiS 187) 



1862 1870 18S(i 1862 1870 1880 



Jan 0.0 -0.2 —0.:-! July 0.6 0.;') 0.2 



Feb 0.0 — 0.1 — 0.2 Au^ 0.9 0.9 0.6 



Mar 0.0 0.1 — 0.1 Sept 0.6 O.r. 0.3 



Apr 0.4 0.4 0.1 Oct 0.:{ o.i -^0.2 



May 0.6 0.5 0.2 Nov 0.2 —0.1 —0.2 



June 0.4 0.4 0.1 Dec 0.1 —0.2 0.0 



After i88i the daily mean of temperature was calculated accord- 

 ing to the formula of Koppen : 



m = n — k ( n — min. ) 



in which 111 represents the true mean temperature: min.= 

 daily minimum of temperature and k a coefficient of which 

 the value is as follows : 



jail o.ioo May 0.209 Sept 0.1S2 



Feb o.ios June 0.215 *^ct 0.164 



Mar 0.143 July 0.217 Nov 0.121 



Apr 0.183 Aug 0.200 Dec O.106 



Precipitation. 



The quantity of rain has heen measured twice daily, morning and 



evening at the following sites : 

 (a) 1864-1870 at the Military Hospital, Stirhei-Voda. 

 ( b ) 1871-1888 at the college of agriculture, Herestrau. 

 (c) 1889-1925 at the Central Meteorological Institute, Filaret. 



RUSSIA 

 Authority. 



Director of the ('entra! (Geophysical Observatory, Leningrad. 

 Material. 



For the time up to 1881 homogeneous observations within the 

 confines of Russia are scarce, and the assurance of similarity 

 of conditions is almost impossible. The data for this reason 

 begin with the year 1881. 



The material from 1881 to 191 5 is checked by the method of 

 difilerences, namely, the construction of mean yearly isobars, 

 analysis of the yearly period, the computation of departures 

 from the means of many years. This work is based on 

 the exhaustive monograph of A. Kaminski on the air pres- 

 sure, on that of Eugenie Ruliinstein on air tem])erature and 

 of E. Berg and A. Tolski on precipitation. 



