From the earliest days of scientific studies on lubrication, the importance of lubricant viscosity has been recognized. The performance of the equipments and machines that use lubricants is decisively influenced by the variation of viscosity depending on pressure and temperature. The paper succinctly presents the installation that has been used, the testing methods as well as part of the measurements. The analysis of experimental results bears out the interdependence between viscosity on the one hand, and pressure- temperature on the other hand. The results are synthetically shown on two tables and three diagrams.
