438 



On the Diselectrification of Air. 

 FIG. 2. 



[Mar. 21, 



FIG. 3. 



Twenty-fire wires to the centimetre. Diameter of each wire is 016mm. Hence each 

 aperture is 0'24 mm. square. 



5. The apparatus is now ready to test the efficacy of filters or 

 other appliances of different kinds placed at F for the purpose of 

 diselectrifying air which has been electrified, whether positively or 

 negatively, by the electrified needle point n. We began with a filter 

 of 12 wire-gauze discs, placed at F and kept in metallic connection 

 with the tin pipe outside. This nearly halved the electricity shown 



