THE GAUSS STATION. 



243 



the "raclisnt, the wind force and the change in wind direction, as the cyclone passes the 

 station. 



There are three variables : 



(a) The velocity at which the cyclone is moving to the east. 



(h) The distance that the centre of the cyclone passes to the north of the station, 

 (c) The time taken for the barometer to fall and rise half an inch. 

 We will at first consider that the cyclone travels at the mean rate deduced by Lockyer, 

 viz., 9 5" of longitude in a day, this leaves us with only two variables, (b) and (c). 



The following table gives the results of a calculation made in this way for four values 

 of (b) and three of (c) : — 



Table 130. 



* Scale given on page 99 of Meinardua. 



