Eliminates capillary depression error. Easily cleaned. Accuracy plus or minus 3%. A tilting gauge which maintains a constant overflow head of mercury and maintains capillary depression of the meniscus. Readings don't bounce. Removable and interchangeable measuring tube permits accurate determination of V1 values; Trubore capillary stem. Minute adjustment of zero line scale position possible. Scales replaceable without recalibration. Mercury resevoir designed for easy pumping and increased mercury storage. Mercury NOT supplied.