Addition of a polarising microscope to the Weissenberg Rheogoniometer

This article describes modifications to a sophisticated commercial rheometer, the Weissenberg Rheogoniometer, to allow a sample in the cone and plate or parallel‐plate geometries to be observed with a high‐quality polarizing microscope. The addition of the microscope does not interfere with the measuring system in any way, so that samples can be observed in the course of rheological experiments.