C70 



REPORTS OF ASTRONOMICAL OBSERVATORIES. 



to repori, when relieved, whether tliey have seeu any auroral lii;ht dur- 

 ing the night ; and if not, whether the sky has been sufficiently clear to 

 permit any to be visible. These records for the past year are presented 

 in the following consolidated table — which, considering the difiiculty of 

 distinguishing the fainter displays, is regarded as establishing the trust- 

 worthy character of the record by the ge::eral accordance between tlie 

 three independent observers. It appears that out of 21G favorable 

 nights, 13 auroras were noted ; and if we may assume the same ratio to 

 apply to the clouded nights, about -J2 auroral displays occurred during 

 the twelve mouths. 



Auroral displays in 1880. 



jSTame of montli. 



.Tanuarv . - - 

 February . . 



March 



April 



May 



Jane 



July 



Ausust ... 

 Scptt-niber. 

 October. ... 

 November. 

 December. . 



Auroras. 



Total for year 13 



0.0 

 0.0 

 1.3 

 1.3 

 0.3 

 0.0 

 1.0 

 3.0 

 1.0 

 2.0 

 3.0 

 0.0 



Clear nights. 



14.7 

 17.3 

 16.3 

 IKO 

 18.7 

 19.3 

 18.3 

 18.0 

 18.3 

 20.7 

 16.0 

 20.0 



213 215.6 



Clouded niiihts. 



^ oi I « I 



10.3 

 11.7 

 14.7 

 12 

 12. 3 

 10.7 

 12.7 

 1.'!. 

 11.7 

 10.3 

 14.0 

 11.0 



143 153 I 150.4 



Summary of auroral ncords for eleven years. 



These observations were undertaken to throw light upon the supposed 

 connection between the number of solar spots and the frequency of 

 auroras and of magnetic disturbances. They have now been continued 

 long enough to give interest to the foregoing summary compiled from 

 the general orders above cited. Ko corresponding record of solar spots 

 during this period of eleven years is at hand for precise comparison ; 

 but such records have been preserved, and they show the number of 



