OF ATMOSPHERIC PRESSURE IN EUROPE, ETC. 259 



inquiry. I have accordingly employed this method in the 

 discussion of a very considerable number of observations 

 made at various places in Europe and Asia, and have 

 obtained results which appear to me to possess considera- 

 ble interest, as indicating very decidedly the existence of a 

 remarkable and hitherto unsuspected law of disturbance of 

 atmospheric pressure, which extends its influence over the 

 greater portion of the European and a considerable portion 

 of the Asiatic continent. 



The following table contains the mean monthly and 

 annual sums of the oscillations of the barometer at seven 

 stations in Europe and six in Asia, as derived from obser- 

 vations extending over periods varying from six to fifteen 

 years. The European stations are Dublin, Sandwick in 

 Orkney, Greenwich, Milan, Stockholm, St. Petersburgh, 

 and Lougan, 48°35'N. 39^20' E. The Asiatic stations 

 are Tiflis, 40°42' N. 44°5o' E, ; Catherinbourg, 56^49' N. 

 6o°35'E.j Barnaoul, 53°2o' N. 83057'E.; Irkoutzk, 52°i7' 

 N. i03°35'E. ; Pekin, 39°54'N. ii6°27'E. ; and Nert- 

 chinsk, 5i°i9'N. ii9°36'E. It must, however, be ob- 

 served, with reference to the results given for Greenwich, 

 that as the individual observations of each day at Green- 

 wich are not given in the published volumes, these results 

 are derived from the daily means, and not from single 

 daily observations as in all the other cases : 



