0>\|H rilVITY AM> I.I MIN"MTY OF FI.AMI.s f( iNTAININC \ Ah MMsl I> MI.Ts lit'.i 



Height of lower edge ... 



of electrodes above j Position of thernio-coii|>li>. '"'J > .lu<ti\ity. 



tip of inner cone. 





It will be seen from the alx>ve table that the temperature registered by the thermo- 

 couple, when l>elow the electrodes, is much higher than when above. The numbers 

 representing the conducting power are otherwise, a slightly lower reading being 

 obtained when the thermo-couple was below the electrodes. This is, of course, due 

 to the cooling effect of the thermo-couple, which in the lower position was immersed 

 in the gases l>efore they reached the electrodes. 



It should l>e stated that the cylindrical column of interconal gases and salt vapour 

 was not appreciably altered by changes in position of the flame tube, so that the 

 i|ii;mtity of salt vapour between the electrodes was sensibly the same in all cases. 



The end result of the above experiments may be expressed as follows : 



These readings are on an arbitrary scale, but they show very clearly that the 

 conducting power increases rapidly with increasing temperature, and that at tempera- 

 tures not greatly below those which the vapour attains in flames the conductivity 

 would become inappreciable. It may be stated that the temperature intervals in the 

 alxtve table correspond approximately to 140 and 95 Centigrade degreea 



Relation between Current Strength and Electromotive Force. 



Experiments on tin- relation between current strength and electromotive force were 

 can UH! out with a large number of salts, and with a difference of potential between 



