VISCOMETRY 'It is a capital mistake to theorise before one has data',Arthur Conan Doyle Introduction Viscometry is the science of the measurement of viscosity'.Such viscometric measurements generally have to do with applying either a force F or a velocity V at a surface in contact with a contained test liquid.The response of this liquid to either the velocity or the force is measured at that surface or at some other nearby surface which is also in contact with the liquid.Examples of the geometries used for this purpose include tubes,parallel plates,cone-and-plate arrangements,and concentric cylinders.Sometimes artefacts arise whereby the presence of these surfaces interferes with the local liquid microstructure,giving apparent slip effects-these will be discussed in detail later