66 



TRANS. OF THE ACAD. OF SCIENCE. 



MONTIILY MEAN OF POSITIVE ATMOSPHERIC ELECTRICITY 

 In 1861. 



January, 

 Febru'vj 



March, 



April, 



May, 



June, 



July, 



August, 



Sept'r, 



October, 



Nov'ber, 



Dec'ber, 



20.3 



13.9 



9.8 



7.1 



8.1 

 4.5 

 4.0 

 3.8 

 4.1 

 8.0 

 10.7 

 15.9 



15.6 

 10.5 

 8.1 

 7.0 

 6.6 

 4.8 

 4.0 

 4.8 

 3.5 

 6.6 

 9.9 

 13.7 



15.2 



11.5 



9.0 



7.7 



<«.2 

 o o . 



AM 



;s5a 



Mean, 8.6 10.0 



9.2 



7.9 



8.7 



12.7 

 8.9 

 8.0 

 9.3 

 7.2 

 3.0 

 3.3 

 2.4 

 1.9 

 6.4 

 7.4 



12.4 



6.9 



16.5 



12.1 

 9.8 

 8.8 

 7.8 

 4.2 

 3.7 

 3 

 3 

 8 



in 



14 





8.5 32 



MONTHLY MEAN OF TEMPERATURE (Thermometer F.) 

 In 1861. 



