The direct current conductivity of polar liquid dielectrics

The increase in viscosity of a polar liquid which occurs when a constant electric field is applied across the capillary in which the liquid is flowing saturates at a high field intensity, and no further viscosity increase occurs (fig. 1(a)). This saturation effect has a long time-constant, and disappears if a very low frequency field of 1 c.p.s. is substituted for the D. C, field (fig. 1(b)); this behaviour is inconsistent with the theory that the viscosity increase is a spurious electrode effect.