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Double bubble trouble?

These mushroom "bubbles" developed about 15 minutes after I topped up a half-full container with...
Double bubble trouble?

These mushroom “bubbles” developed about 15 minutes after I topped up a half-full container with more liquid soap (see photo). The fresh liquid seemed to bounce off the bottom of the container and then mushroom up. Are the principles of surface tension and drag outlined in earlier answers to “Bubble trouble” on 20 June at play here? Or could it be something else?

Lloyd Tregenza, Adelaide, South Australia

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