(9) At the point where a line of force intersects the perpendicular bisector of the axis r=r'=r o, say, and cos 0 - cos 0 obviously =l/r o, l being FIG.
Bisector, from bi-, two, secare, to cut), in geometry, the same as bisector, i.e.
If now a line be drawn from A to the bisector H of the side BC, it will meet the vertical through G in I and IJ =c(cos a+a sin a)/ur.
5) is the direction of a ray, either from a heavenly body or from a terrestrial point, impinging at 0 upon the surface of quicksilver, and reflected in the direction OR, the vertical line is the bisector OZ, of the angle POR.
In the case of a biaxal plate perpendicular to the bisector of the acute angle between the optic axes, the curves of constant retardation are approximately Cassini's ovals, and the lines of like polarization are equilateral hyperbolae passing through the points corresponding to the optic axes.