A tilting gauge with a constant zero overflow which eliminates the capillary-depression error from an expanding meniscus. Once the zero line of the scale is aligned with the tip of the closed capillary, it is only necessary to bring the gauge to an upright position and read the scale behind the closed leg. Gauges are fabricated from calibrated ACE Trubore tubing, to assure uniform and reproducible reading between the gauges. Mercury trap is incorporated in female joint, bulbs are enlarged. Joint is standard taper 20/65. Mercury NOT supplied.