1905.] PUBLIC DOCUMENT — No. 83. 



27 



Table V. — Eecotrh shoioituj Ihc Electrical Potential ( Volts) taken from 

 an Elm Tree and from Eree Air — Continued. 



[Collector III., 12 feet high, in Norway spruce. Nos. IV. and V., readings taken from 

 copper plates in soil. Time of observation, 9 a.m.] 



Septeml)er 6, possibly slight movement toward positive in Nos. III., IV. and V. 

 Operator away from September 10 to September 25. 



