344 EXPERIMENTAL INVESTIGATIONS. 



the kindness of Mr. Gassiot to repeat this experiment with 

 his battery of 500 well-insulated cells of the nitric acid com- 

 bination, air did not conduct when the ignited wires were ap- 

 proximated to the g-V tn f an mcn > on approaching them 

 nearer they came within striking distance, were instantly fused, 

 and the galvanometer needle, which had up to this time been 

 perfectly stationary, was whirled rapidly round. 



Fig- 3- 





I think I am entitled to conclude from this that we have 

 no experimental evidence that matter in the gaseous state 

 conducts voltaic electricity ; probably gases do not conduct 

 Franklinic electricity, as the experiments which would seem 

 primd facie to lead to that conclusion are explicable as 

 resulting from the disruptive discharge. 



In Faraday's experiment two wires were approximated in 

 the flame of a spirit-lamp, and a slight conduction across 

 the interval in the flame was observed. This conduction 

 might have been due to certain unconsumed particles of car- 

 bon existing in the flame, or possibly to the flame itself. 

 According to Dr. Andrews, flame, even that of pure hydrogen 

 gas, conducts voltaic electricity.* 



I now endeavoured to ascertain whether any specific in- 

 ductive effect of the hydrogen might have an influence : paral- 

 lel wires of platinum and parallel coiled copper wires were 

 placed in atmospheres of hydrogen and of atmospheric air, one 

 of which parallel wires conveyed the curre.it, and the other 

 wire was connected with a delicate galvanometer.f I could 

 detect no difference in the arcs of deflection of the needle at 

 the instant of meeting or breaking contact, whether the wires 

 were in atmospheres of hydrogen or of atmospheric air ; nor 

 when parallel platinum wires, with their surrounding atmo- 

 spheres of gas, were immersed in a given quantity of water, 



* Phil. Mag., vol. ix., p. 176. 



f I have obtained a slight effect on the galvanometer in a circuit with interposed 

 parallel wires ignited in the vacuum of a good air-pump. Quare, whether this is 

 true conduction or a disruptive effect. W.R.G., 1874. 



