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Mr Townsend, On Electricity in Gases [Feb. 8, 



through the tube containing the glass wool, and if this be now 

 replaced on the end of the indiarubber tubing it will be found 

 impossible by blowing unelectrified air into I to displace any 

 of the charge that had been put in after it had been there for the 

 space of half a minute. 



We have a simple explanation of this result by supposing the 

 charge to be distributed over a small number of carriers, each 

 having a relatively large charge, but in the case of a gas with an 

 equal electrification per c.c, the number of carriers is very much 

 larger and the charge on each proportionally smaller, being 

 probably the atomic charge, so that the force due to their mutual 

 repulsion which acts on each carrier would be small, and con- 

 sequently a long time would elapse before they would reach the 

 sides of the vessel. This property of a charged gas can be 

 illustrated by the following experiment. 



5. The electrification of hydrogen which is given off when a 

 metal is dissolving in an acid can be seen by pouring a 50 per cent, 

 solution of sulphuric acid, at a temperature of about 80°, over the 

 iron wire contained in the vessel A, fig. 1. The hydrogen as it is 

 given off is made to bubble through permanganate of potash in B, 



Fig. 1. 

 (The dotted lines represent insulators.) 



and through sulphuric acid in C, and then to pass through a 

 tube of glass wool W before entering /, which is connected to the 



