Importance of wind.

The wind is extremely important in terms of driving the narrative, since Mary Poppins both arrives with and departs with a strong wind outside of Number Seventeen. The wind symbolizes inevitable change, as nature, just like a human life, is often directed by the course of sporadic and yet predictable patterns of change. Just as the seasons alternate, and humans grow, the direction of the wind changes and so alters the course of certain natural elements and courses of events. Mary Poppins' departure with the wind is therefore lent a certain sense of inevitability and is made to feel part of a greater course of Earthly events and processes.