This paper presents direct measurements of multiphase plumes in stratification and correlates characteristic plume properties with the nondimensional slip velocity UN . UN is defined as the ratio of the bubble slip velocity us to a characteristic plume fluid rise velocity (BN)1∕4 ; B is the total kinematic buoyancy flux, and N is the buoyancy frequency. UN is derived by dimensional analysis and is compared to other nondimensional parameters for multiphase plumes in the literature. To investigate correlations of the nondimensional numbers with plume properties, laboratory experiments were conducted in linear stratification using dispersed phases of air, oil, and glass beads (creating an inverted plume). A new type of plume behavior is identified, called Type 1* , in which the horizontal motion in the first detrainment event disperses the relatively weak bubbles, creating a diffuse bubble plume that forms out of the intrusion. Measurements from these and previous experiments for type behavior, trap height, ...