1= 1+ 4πne³Hp,
v1² m² (s² − p²)²
1= 1 4πne³Hp.
v2² m² (s² − p²)²

The rotation r of the plane of polarization per unit length

= ½p ( 1 1) = 2πne³Hp²v.
v1 v2m² (s² − p²)²

Since 1/v² = K0 + 4πne²/m (s² − p²), we have if µ is the refractive index for light of frequency p, and v0 the velocity of light in vacuo.

µ² − 1 = 4πne²v0² / m (s² − p²).

(1)

So that we may put

r = (µ² − 1)² p²H / sπµnev0³.

(2)