A. W. Wright on the discharge of the Electrical Machine. 383 
tex of the positive pole. The corner apertures in this case be- 
ing more distant from the axis, had their images somewhat dis- 
torted, so that the sides of the square were represented by lines 
curved in such a way as to make the angles at the corners acute, 
just as it would happen if the square should be stretched in the 
direction of its diagonals. 
Very frequently, in fact usually, the jet does not issue from 
the vertex of the negative, but is displaced to the one side or ~ 
the other. In such eases the glow is also displaced in a similar 
manner, that is, so that its axis is inclined at an equal angle to 
the line between the poles with that of the negative jet. If the 
grating is placed before the latter, and perpendicular to it, the 
shadows are still formed as eens though not in general quite 
if place 
ecient semee,, 
-_ edi. 
J ~ 
appears at b, On moving it 
away from the pole to a posi- 
tion the Ae i 
age still appears at 6, but is 
point of one of the poles, a line in a curve to the homol- 
ogous point on the other pole, where also it meets the surface 
normally. When the jet is not far from perpendicular to the 
line of the poles, the curve may have an amplitude of nearly or 
quite half the distance between the latter, even when these are 
eight inches, or more, apart. 
