26o Dr. Schuster on 



discussed at length in a paper (Proc. Roy. Soc.^ XXV., p. 102, 

 1877), and the result seems decidedly in favour of such a 

 connexion, especially in the winter months. During the 

 period 1855-65, as well as during the succeeding ten years, 

 the temperature range, which is the difference between the 

 highest and lowest value of temperature during any given 

 day, shows a minimum at full moon, and a maximum shortly 

 after new moon. It is strange, however, that the researches 

 of Baxendell {Proc. Man. Lit. and Phil. Soc, Session 1879), 

 from observations taken at Southport, have led to a directly 

 opposite result. Baxendell does not give his calculations 

 as interfering in any way with Stewart's result, but rather 

 as tending to show that the influence may be different at 

 different places. It is easy to see, in fact, that if the lunar 

 influence affects, in the first place, the distribution of pressure 

 ■over the globe, so that the path of atmospheric depressions 

 is altered, an increase of temperature range at one place 

 might be coincident with a decrease at another. Neverthe- 

 less, the marked difference in behaviour between two 

 places not further apart than Kew and Southport, show the 

 desirability of further researches ; and now that a connexion 

 between the frequency of thunderstorms and the phases of 

 the moon has been shown to exist by Koeppen and others, 

 the subject no doubt will receive renewed attention. 



The daily range of magnetic declination is a quantity 

 similar to that of the daily range of temperature, and 

 Stewart has frequently taken it as the basis for his reduc- 

 tions. The daily range exhibits also a lunar period having 

 a maximum both at full and new ir[oon(Proc.Roy. Soc. XXVI, 

 1877). A similar result had been previously obtained by 

 Mr. Capello, the Director of the Lisbon Observatory. 



The same paper contains another investigation. 



The sun spot variation which apparently depends on 

 planetary configuration suggested a search for a similar 

 variation of declination range. It appeared from the result 



