422 Prof. Phillips's Observations of Temperature [April 4, 



During the late partial eclipse of the sun on the 6th of March 1867, 

 observations of the ingress of the moon were favoured at Oxford by bril- 

 liant weather ; within fire minutes after the moment of maximum obscura- 

 tion ^ clouds appeared ; and from this time till the end of the eclipse 



they never wholly disappeared, but did not prevent the progress of the 

 moon and the degrees of obscuration from being correctly marked. At 

 the very end it was only just possible to observe the egress by a momentary 

 attenuation of the clouds ; the remainder of the day was cold, cloudy, and 

 finally snowy. The observations began at and ended at 10^ 50°", thus 

 including the whole period of the eclipse, which began at 8^ 15^ reached 

 the greatest obscuration at 9^ 26°", and ceased at 10^ 45"^ 8^ At the mo- 

 ment of greatest obscuration the light-giving area was reduced to one-third 

 of the solar disk. 



The observations comprised — 



(1) Temperature in the shade, by the mean of one mercurial and one 

 spirit thermometer very nearly agreeing throughout. 



(2) Temperature in the sunlight, by a clear mercurial bulb. 



(3) Temperature in the sunhght, by a dark mercurial bulb. 



(4) Temperature in the sunhght, by a dark mercurial bulb enclosed in 

 a glass tube exhausted of air. 



The observations were recorded at intervals according to convenience 

 (3°" to 20"^), the shorter intervals being purposely chosen about the time of 

 maximum obscuration. The results are in the following Table : — 



1 



Thermo- 



Clear 



Dark 



Dark 

 bulb in 

 glass 

 tube. 





1 Hour. 



meter in 



bulb in 



bulb in 



Eemarks. 





shade. 



sun. 



sun. 





h m 



35-5 



39-5 











8 



41-0 



54-0 



Sky always clear tiU the 



12 



Beginning of eclip 



se. 





middle of the eclipse. 



25 



36-2 



44-0 



48-0 



58-8 



45 



36-7 



44-0 



46-5 



57-8 





9 



36-7 



43-6 



46-5 



52-0 





18 



36-7 



41-5 



43-0 



46-5 





25 



36-7 



40-5 



430 



43-5 





26 



This was the moment of greatest obscuration. 



32 



36-7 



41-5 



43-2 



42-9 



Clouds gathered at 



35 



36-7 



38-0 



38-0 



410 



30™ and continued 



50 





40-0 



40-5 



420 



to the end of the 



10 





40-0 



41-0 



43-3 



eclipse. 



15 



37-7 



42-5 



44-5 



46-8 





35 





_42-7 



44-0 



49-9 





45 



End of e 



clipse. 









50 



38-8 



420 



43-0 



50-0 





Mean... 



, 37-2 



41-5 



43-2 



48-4 





Max. ... 



38-8 



44-0 



48-0 



58-8 . 





Min. ... 



35-5 



38-0 



38-0 



41-0 





Eange .. 



3-3 



60 



10-0 



17-8 





