ELECTRIFICATION OF AIR, VAPOUR OF WATER, AND OTHER GASES. 195 



ELECTRIFICATION OF AIR BY WATER JET ( 25-37). 



25. In previous experiments* we found air to be negatively electrified by water 

 falling in drops through it, and to pursue the investigation further the arrangement 

 shown in fig. 3 was put up. Loch Katrine water, under full pressure, issues from a 



Fig. 3. 



jet, J, fixed in the lid of a funnel, F, and falls down the funnel centrally into a metal 

 can, C, below. By means of an air-pump some of the air is withdrawn from the can 

 or funnel through metallic tubing, as shown in the diagram, to a metallic filter, AB, 

 containing 50 fine brass wire gauzes. In each experiment 200 strokes of the pump 

 are taken. 



* " Electrification of Air by Water Jet," by MACLEAN and GOTO. ' Phil. Mag.,' August, 1890. 

 " Electrification of Air," by Lord KELVIN and MAGXUS MACLEAN. ' Proc. Roy. Soc.,' May, 1894. 



2 C 2 



