the Hot Gases from Flames. 



35 



Conductivity 



Distance from 



Time from flame 



proportional to 



Hanie in cm. 



proportional to 



50 



9 



18 



25 



14 



28 



14 



19 



39 



8-5 



24 



51 



6-5 



31 



69 



6 



34 



77 

















Fig. - 



i. — Curve 



IV. 























\ 

































l J 



































\\ 























































'-3 







I 



4H 





















3 

 § 







! 





\ 





















u 

















^ 



B 





































-„ 









































--_ 

















* 





































20 



30 40 50 



Time from flame. 



60 



80 



Curve IV. a is plotted from the above numbers, and shows 

 the way in which the conductivity falls away, owing to the 

 recombination of the positive and negative carriers. 



The rate at which the conductivity falls away evidently 

 diminishes with the conductivity. If n be the number of 

 ions per unit volume at any time, and if we assume that 



dn „ 



-Tt =an > 



we get 



n W 



where N = number of ions when £ = 0. 



If we use the points A and B on the curve a to determine 

 the constants in the above equation and plot the curve, we 

 get the curve b. 

 S D2 



