132 M.A.Kxjpf^efs Note an the Mean Temperature of Nicolaieff 



tte spring equinox, on the same days and at the same hours 

 at >vhich M. Kupffer observed at St. Petersburg. I have also 

 determined the intensity of the terrestrial magnetic forces 

 at Pekin, and at other points of my journey. 



" Relative to the geographical position of Pekin, I have ob- 

 served, 1st, eleven transits of the moon by the transit instru- 

 ment ; 2ndly, a central eclipse of a Tauri by the moon, with 

 the great telescope of DoUond; 3rdly, during twelve days 

 from the winter solstice to the present time, the height of the 

 sun at noon for the determination of the latitude, which I have 

 found to be nearly 39° 54' 9"; and, 4thly, ten times, the transits 

 of different stars across the plane of the prime vertical, to de- 

 duce the latitude according to the method of Bessel. 



" I have observed also since my arrival, four times a day, thp 

 state of the barometer and thermometer. The greatest baro- 

 metric height of 3i5-l French lines took place on the 8th of 

 March at midnight; and I am informed that on the same day, 

 in the northern provinces, there was felt an earthquake. The 

 smallest barometric height took place on the 20th of April, at 

 six in the evening : it was 330-9 lines, and it was followed by 

 a' tempest. The greatest heat which has yet taken place was 

 on the 20th of April, at ^'^ p.m. : it was 25° cent. The greatest 

 cold was 13" cent.: it took place on the 5th of February, at 

 6'' A.M. In the same month, however, on the 17th, the tempera- 

 ture rose even to 10°-5 cent. The cold was constant during 

 the second half of the month of January : in the other hali^ 

 as in the month of December and the beginning of the month 

 of February, the temperature oscillated round the point of the 

 congelation of water; since the 13th of March it has been 

 constandy warm. A barometer and thermometer will remain 

 at Pekin, which will be observed during the ten years that the 

 Mission will remain in China*." 



XXX. Note on the Mean Temperature of Nicolaieff, as de- 

 duced from the Observations of' M. Coumani. Bi/ Professor 

 M. A. Kupffer, of the Imperial Academy of St. Petersburg.\ 



COUMANI, at Nicolaieff, has communicated at differ- 

 enttimes to the Academy of Sciences at St. Petersburg, 

 meteorological observations, carried on by himself, and through 

 his means, with a perseverance, well worthy of imitation, at 

 Nicolaieff and Sevastopol. These observations are reduced 

 with much order, and to the register of each month is ap- 

 nexed a very elegant graphical view of the results. 



"• AH the dates in this letter are rep^one^ by the New Style, 

 t Communicated by the Author. 



M. 



