68 



REPORT — 1886. 



meteorological element, and that of the magnetic inclination, ^ as shown 

 in the following curves. 



It will be very difficult to say what direct connection there can be 

 between the tension of vapour and the magnetic inclination, but the great 

 similarity of the carves (month by month), and also in the different 



-+-D'IURNAL--VARIAJION^OF-VflPOUR-TENSION 



reasons (although the phases of the inclination are nearly two hours 

 earlier) make one think that at least the causes of the variations of these 

 heterogeneous elements are the same. 



One would therefore attribute to the currents of the atmosphere the 

 magnetic variations : can it be that the vertical currents which are sup- 



