436 



Mr. A. Tribe. 



[June 16.. 



trodes, and consequently perpendicular to the direction of the influence- 

 Distributions having these characteristics are named parallel. Tho 

 dotted lines in the figure represent the boundary lines and the arrows 

 the course of the energy. 



ft. When the course of the energy is parallel with the sides of an 

 analyser, bat makes with its edges an oblique angle, the boundary lines 

 of the ions are still parallel with the plane of the electrodes, but 

 necessarily cross the sides of the plate obliquely to its edges. This 

 obliquity varies proportionately with the angle of inclination of the 

 analyser to the energy, so that in all cases the boundary lines are per- 

 pendicular to the direction of its transmission. 







- 









1 



X - 



— 







> 



7. When the course of the energy makes an oblique angle with the 

 sides of the analyser, neither the magnitude nor the boundary configu- 

 ration of the same electrification is identical on the two sides of the 

 plate. The boundary of the positive ion on the side in opposition to* 

 the direct course of the influence is now markedly convex, and greater 

 in magnitude than on the reverse side, where, moreover, the boundary 

 configuration of the same ion is markedly concave. Again, the 

 boundary line of the negative ion on the first-named side of the 

 analyser is concave and smaller in magnitude than on the reverse side, 

 where the boundary of this ion is convex. The convexity and con- 

 cavity of these several boundaries increase as the direction of the 

 energy approaches a perpendicular to the sides of the analyser. Both 

 the classes of distributions described in j3 and 7 are named non- 

 parallel. 



The position of the ions on an analyser, and the character of their 

 boundary lines determine then, and with accuracy, the direction of the 

 energy in the electrolytic field relatively to either side or edge of tho 

 analysing plate. 



