(6) From the geometrical dimension of hollow cylinder used for the torsional vibration we can determine four constants (3^*), (2^*), (1^*) and (0^*) and from the logarithmic decrement δ and period T of vibration, as well as from the density ρ of liquid, we can calculate by (18)
(3)=(3^*)η, (2)=(2^*) (B-Aη), (1)=(1^*)/ρ, (0)=(0^*)A/ρ²,
and thence
ξ₁=(2)/2(1)[1-√<1-4(1)(3)/(2)²>], ε(0)ξ³¹/[-(2)+2(1)ξ₁-3(0)ξ²₁].
The viscosity μ of the liquid can be then calculated by
μ=(ξ₁+ε)²/(πρT)