the late Balfour Stewart. 259 



Rev. S. J. Perry, Director of the Stonyhurst Observatory, 

 has since paid considerable attention to this point, and in 

 joint communication with Balfour Stewart, some preliminary 

 results are given {Pi'oc. Roy. Soc. XXXIX., p. 363, 1885). 



The conclusions of the investigation are ^w^w in these 

 words : — 



(i) In the very great majority of cases the angular value 

 the declination disturbance is greater for Stonyhurst than 

 for Kew. 



S 



(2) The ratio -p is certainly greater for disturbances of 



short than for those of long duration. Our observations 

 are not, however, sufficiently extensive to enable us to 

 represent this ratio graphicall}' as a function of the 

 duration. 



(3) As far as we can tell from a limited number of 

 observations the value of the above ratio does not depend 

 on the magnitude of the disturbance. 



I now turn to that part of Stewart's work in which he 

 was principally interested at the time of his death, namel}% 

 the phenomena of sunspots and their connexion with plane- 

 tary configurations and terrestrial meteorolog}-. 



In a paper published jointly with Dr. Warren de la Rue 

 and Mr. Benjamin Loewy, the size of a sun spot or group of 

 spots is investigated in its passage across the solar disk, in 

 order to determine whether the size varied as some meri- 

 dian opposite one of the planets is traversed. Definite 

 results were obtained for the planets Mercury and Venus ; 

 the average size of a spot in both cases being smallest on 

 that side of the sun which is directly under the planet, and 

 largest 180" away from that point. As regards Venus the 

 result appears both from the observation of Carrington and 

 those taken at Kew. 



The question of a possible connexion between the 

 temperature range at Kew and the phases of the moon is 



