WISLIZENUS ATMOSPHERIC BLECTRICITY. 



169 



4. — Direction of Wind from 1861-1872 at St. Louis, Mo. 



Percentage of Direction of Wind during the Twelve Years^ in the 

 different Months- 



REMARKS. 



The foregoing tables give a summary of my observations, dur- 

 ing 12 years, of positive atmospheric electricity, with the correla- 

 tive observations of temperature, of humidity, and of direction of 

 winds, so that the reader may judge himself to what extent those 

 meteorological phenomena influence electricity. 



The electrical observations were made in the same way as de- 

 scribed by me in the Transactions of the Academy ., vol. ii., with 

 Dellmann's apparatus, and without any change in the fine glass- 

 thread of the measuring instrument. The movable collecting ap- 

 paratus of Dellmann seems to me far preferable to any stationary 

 instrument, because the first develops the momentary electricity 

 of the atmosphere, and the latter that collected and accumulated 

 for some time. But his measuring apparatus is too delicate to be 

 moved ; and if it could be supplanted by an instrument as deli- 

 cate in action but of easier transportation, electrical observations 

 would become more general and their results more valuable. 

 Local meteorological observations are certainly useful and instruc- 

 tive ; but meteorology, as a theoretical and practical science, will 

 attain its <:limax only when spread as a net-work over the whole 



