128 DE. W. G. DUFFIELD, MESSES. THOS. H. BUENHAM AND A. H. DAVIS ON 



For example, in fig. 15, Series B, instead of 0'45 dynes being the pressure at 

 5 amperes it is I'O dynes, since if produced backwards the curve cuts the vertical 

 axis at 5 '5 dynes. 



The curves for Series B have been represented by straight lines wherever possible, 

 but it is obvious that the points are often better represented by curves slightly 



z-o 







o, 



0-=, - 



-0-5- 



Correctiou 

 for convexion 

 currents 



T~ "To 



Amperes 



Negative pressure 

 due to convexion 

 currents 



D 



Fig. 22. For " observed " curve, see fig. 14. 



convex to the current axis ; they are subject to the same corrections as Series C, 

 and they become more nearly straight after allowance is made for convexion 

 currents. 



In Table X. are shown the values of the pressures corrected for convexion currents 

 for arcs of 10 amperes and 6 mm. length. We shall make further use of these values 

 in a later section. % 



