How does Wilde make the audience at the end of Act 1 wonder what may happen next
After Gwendolyn returns from speaking with her mother in the waiting carriage, she asks Jack where his country home is located, and he gives her the address. Off to the side by the fireplace, an eavesdropping Algernon quietly smiles to himself and pencils the address on his starched shirt-cuff, and then he picks up the Railway Guide. It seems that he may wish to see how to travel there for his own personal reasons since Jack has previously told him of his eighteen-year-old ward Cecily.
This episode is but one of many in which Oscar Wilde satirizes Victorian society, especially with the pun on the title as Victorian society purportedly valued sincerity and earnestness. Clearly, Wilde ridicules the "earnestness" of the upper class with the duplicity of Algernon and the values of others such as Gwendolyn's mother, who questions Jack and rejects him because he was a foundling, urging him to "produce at any rate one parent" in order to be considered as a suitor for her daughter.