58 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 79 



September 1882 to Septenil^er 1887 the observations were 

 made at the hotel (Gasthaus) some 40 m. below the summit, 

 height 2465 m. From October 1887 to 1920 they were made 

 at the observatory on the top of the mountain. 

 Pressure. 



All the observations are reduced to the height of 2500.1 m. The 

 correction for gravity (0.16 mm.) is not applied. From 1883 

 to 1887 the pressures are about 2 mm. too low. 



The means throughout refer to 7^30", 13'' 30™ and 21^30™ 

 Central European time. The instrumental errors were deter- 

 mined for the entire period. The heights were measured 

 from the well determined fixed point, Pierre du Niton, at 

 Genf. (Geneva), 373.6 m. above sea-level. 

 Temperature. 



The exposures of the thermometers from October 1888 to 1893 

 were not entirely satisfactory. 



ZURICH 



Authority. 



Swiss Meteorological Service. 



Site. 



The meteorological station during its entire existence has been 

 in a valley toward the northwest side of Ziirichberg at no 

 great height above the level of the lake and the Limmat plain. 

 From 1864 to 1890 the station was at the astronomical ob- 

 servatory of Ziirichberg, the height of the thermometers 

 470 m. From 1891 to 1920 the station was in the Physics 

 Building (near the observatory), the height of the ther- 

 mometers 477 m. 



Pressure. 



The means have all been reduced to a height of 493.2 m. The 

 ]:>ressure is not reduced to Lat. 45°. The correction is 0.08 

 mm. On January i, 1890 a new series of observations were 

 begun at the Physics building. The old series (1864-1889) 

 leaves something to be desired in homogeneity. 



Temperature. 



From 1 864- 1 873 the thermometers were exposed in a zinc screen 

 on the north side of the tower about i^ m. above the sod. 

 From 1874-1890 they were in a zinc screen inside of a 

 wooden shelter. From 1891-1895 (September) they were in 

 a wooden screen on the path in front of the Physics building. 

 .Since October 1895 they have been in an iron shelter at the 

 same ])Iace. 



