446 



REPORT 1884. 



Steoxtium — continued. 



Becquerel has observed infra-red lines at 8700, 9G10, 10030, 10310, and 10980 in 

 the Arc Spectrum of Strontium. 



On the Connection between Sunapota and Terrestrial Phenomena. 1 

 By Professor .Sciicstkr, F.R.S. 



[A communication ordered by the General Committee to be printed in extenso 



among the Eeports.] 



[Tlates I.— III.] 



The very remarkable connection between the state of tbe solar surface 

 and magnetic phenomena on tbe earth has naturally suggested the ques- 

 tion whether other meteorological phenomena show a similar relationship. 

 The older speculations which date back almost to the discovery of sun- 

 spots were revived, and an opportunity was once more given to the 

 meteorologists to prove the often questioned utility of tbeir long-con- 

 tinued series of thermometer and barometer readings. They have made 

 use of this opportunity, and we shall see wbat the result of their labours 

 has been. 



It may be well to state at once what, in my opinion, we are and what 

 we are not to discuss to-day. We have not come here to discuss the 

 a priori probability of a connection between sunspots and the weather, 

 or, as it is often erroneously expressed, an influence of sunspots on the 

 weather. The only question before us is the proof or disproof of such a 



1 This paper was read in order to initiate a special discussion on the Connection 

 of Sunspots with Terrestrial Phenomena, on the morning: of Monday, September 1. 

 The following paper by Professor O. J. Lodge initiated a similar discussion on 

 Friday, August 29, on the Seat of the Electromotive Force in the Voltaic Cell. 



