Test Method :- These viscometers are used to determine the viscosity of petroleum products. Two adoption of red wood viscometer are available no. 1 for liquids having red wood flow 20 seconds to 2000 seconds and no. 2 for liquids whose flow time exceeds 2000 seconds and no. 2 for liquids whose flow time exceeds 2000 seconds. Redwood viscometer is used for the determination of redwood viscosity and which can be converted to kinematic viscosity also. It is also used for observing the effect of temperature on viscosity by plotting graph.