ABSTRACT
Soap films minimize their film area if atmospheric pressure exists on either side. A soap bubble in three dimensions tries to minimize the enclosed volume. Thus a single soap bubble constrained between parallel plates will be very precisely cylindrical. One of the parallel edges of the prism also forms one of the shorter edges of the rectangle. The film pattern retains one mirror plane. The chapter describes bubbles in fixed and variable frameworks, coalescing bubbles and bubbles in froth. Analogy is made between patterns within a bubble raft and crystal structures. Considerable variation of size and shape of bubble is possible within the variable frameworks, which provide an interesting method of looking at the divisioning and coalescing of bubbles. The bubbles can grow or shrink over an extended period of time by the diffusion of gas from nearest neighbours, such that a dynamic system evolves.
