UNCLE SAM'S FARM. 229 



ground, and the attracting influence is instantly felt. 

 Let the point when bent down be connected with a 

 delicate galvanometer in such a way that the current 

 will pass across the needle, and it will be deflected 

 several degrees. Place in each hand a piece of oiled 

 silk, so that the hands may be insulated while in con- 

 tact with the instrument, and it will remain entirely 

 passive, though it may be directly over the attracting 

 influcDces. 



These experiments of themselves abundantly show 

 that the phenomenon is due to electrical excitation, 

 and to this department of natural science are we to 

 look for an explanation of this interesting matter. 

 In a future communication I will mention some other 

 experiments, and perhaps venture upon an hypothesis 

 in explanation of this singular and unexplained phe- 

 nomenon. 



