The maximum liquid drop volume (v(max)) is measured by using a back-suction micrometer syringe piston technique. Different very viscous liquids are measured by (v(max)) and (vf) methods to observe the effect of viscosity on tension measurement. No apparent viscosity effect was observed in surface tension data obtained by using Harkins-Brown factors and the theoretical correction factors in the viscosity range 5.9-100,900 mP.