Describe how shaw uses the rain as a plot device in the opening act

Shaw uses it not only to bring all the main characters together but also to get people from all walks of life in london together. He got a wide variety of people around which he could have developed a whole new play. Only a necessity of shelter of rain could have made sure that the rich and the poor, the educatedand the uneducated, the 'saints' and the crooks 'could' have assembled together.If not for the rain, all these people would not likely be found in the same place.

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