A bubble chamber designed to operate with 500 visible liters of liquid hydrogen has been tested for performance with liquid nitrogen at Argonne National Laboratory. It features unique systems for controlling chamber overpressure and minimizing thermal gradients within the working liquid. Refrigeration requirements were determined for the full range of operating conditions from static to expansion‐pulsing at a rate of 3/sec at intervals ranging from 333 msec down to 125 msec.