458 Prof. W. M. Thornton on the Ignition of 



7. Ignition by Alternating Current Break Sparks. 



The curves of figs. 6 to 9 contain the results obtained by 

 the use of alternating currents at a frequency of 36 and a 

 voltage of 200. There is a general modification of the 

 shapes of the curves of considerable interest in its bearing 

 on the views advanced in the last two sections. 



AMPERES A-C 











\ 









i ' | 











Pi 



G.6.- 



ROGf 



! 



1 / 







HYD 



:n 















! 



1 







[ 



1 ! ! 









V 



1 















j 











1 



4- -6 -Q l-O S-Z I-* 





w 

















Fl 



G.7. - 

 "HANE 







\ 





MEl 









\ 















\ 













i 



V 



X. 



















- 



i 













-2 -4- -6 Q l-O »2- h 



1Q 







VI 









i-s 





:\\ 





i 



FlC Q 









\ 





PROPANE 



I 



In 



• k ! _ 









! 



\ 











\ 





•5 



i 



i 









1 



i 











i • ! 



! 1 i 









l-O 12. 



Hydrogen no longer has the extreme oscillation of fig. 1, 

 and the extent to which it has been wiped out is an indication 

 of the change in the relative values of the two phases, in 

 which heat and ionization are respectively dominant. The 



