64 



Mr. J. Enright on Electrifications due 



Zinc dropped into acid. Insulated quads con 



nected to insulated generator 



Spot moving to left. Generator positive 



Spot moving faster 



Insulated quads and insulated generator discon- 

 nected 



Insulated quads and generator reconnected . . 



Spot stops and appears to return 



Spot crossed zero 



Quads and generator disconnected 



Quads and generator reconnected 



Effervescence gets less 



Quads short-circuited 



Time. 



h 



m 



I 2 



2 



10 



14 



2 

 2 



16 

 17 



\* 



18J 



2 



19* 



2 



20 



2 



21 



2 



21* 



2 



23 



2 



25 



2 



26 



2 



26* 



2 



28 



2 



31* 



2 



33 



2 



33* 



2 



35 



2 



37 



2 



40 



2 



42 



Reading. 



378 (zero) 



377 



367 

 360 



319 



349 



329 

 322 

 319 



328 

 346 

 366 

 378 

 388 

 458 

 458 

 513 

 550 

 562 

 568 

 382 (zero) 



It may yet be urged that when hydrogen passes through 

 hydrochloric acid, it carries with it both HC1 gas and vapour 

 of water, and that the electrification is due to these, and not to 

 the hydrogen. In order to test the suggestion, I placed on 

 the insulated plate a dish nearly filled with boiling concentrated 

 HC1. In two minutes the plate was connected with the insu- 

 lated quads, but the spot moved only 1 or 2 divisions. It was 

 then watched for more than 5 minutes, but the spot did not 

 stir although clouds of vapour were escaping from the acid. 



I cannot help remarking on the difficulty of neutralizing 

 a gas — at all events, hydrogen. The following experiment is 

 well calculated to illustrate this properly, while it affords, I 

 submit, a very stringent verification of the experiment to 

 which the notes are appended. The large beaker with the 

 small dish was set up in the manner described in the experi- 

 ment just referred to. The dish was nearly filled with a 16- 

 per-cent. solution of HC1 in distilled water. Three small 

 fragments of zinc were thrown into it. A disk of sheet- zinc 

 with a circle one inch in diameter, cut from its centre, was 

 placed as a cover on the beaker. Over the aperture in the 

 centre were placed, one above the other, 4 flat pieces of per- 

 forated zinc, the perforations being ^ of an inch in diameter. 

 The hydrogen had to fight its way through this barrier, and 



