The rising of air bubbles released in distilled water beneath na imiscible Newtoniam fluid was studied in an imiscible Newtonian fluid was fluid ws studied in this work. The properties of the upper fluid were modified and rising of the bubble in each of the six different fluids was noted. There were thereee types of behavior witch were a function of the bubbles diameter: a)Small size bubbles: remained temporary ar the interface and then rise upper phase without any perceptible water element envelopping them Limit: D less than 3,4 more or less 0,2 mm b)Medium size bubbles: passes directly through the liquid-liquid interface and now enveloped with a waer layer of variable thikness rise in the upper phase and reach the free surface with the coating intact. The medium size bubbles rise at a distance of over 50D. Limit: 3,4 more or less 0,2 mm less than D less than 5,5 more or less 0,3 mm c)Large size bubbles: passed directly trrough the liquid interface. At a certain height above the interface the water layer datached from the air bubbles. Limit: D more than 5,5 more or less 0,2 mm The critical diameters were found to depend on the viscosity of the upper phase. This study was restrict to cases b and c where the large influence of the envelopping water layer datached from the air bubble. This study was restrict to cases b and c where the large influence of the envelopping water layer over the air bubble was observed. The change of the visconsity value has an influence on : (a) the way in which the bubble and the water layer and; (b) the way in which the bubble lift the the water layer and (c) the detachment between the bubble and the water layer. For fluid of high viscosity, the passage is slow and makes a liquid colimn that breakes into passage is slow and makes a liquid column that breakes into droplets and the detachmenr of the water layer is smooth. For liquid os samall viscosity this transitional behavior is the oppoite. The detachment is violent. The curves which describe the height of detachment as function of the diameter, for each one fo the upper liquids show that: for a given diameter also have a inverse variation. The investigation made to measure the water mass transfer phenomena caused by the bubbles showed that the mass transfer will be larger for the higher viscosity fluides and the larger diameter bubbles.