The extract belongs to the last part of the 18th chapter of "Ulysses". This episode is called "Penelope" and belongs to the 5th section.
In this extract the time is not fixed: in Molly's interior monologue she shifts from present to future and past: from the alarm clock to the description of Gibraltar during her youth and the dialogue with her future husband.
The technique Joyce uses to tell her thoughts is the "female interior monologue", a sort of "stream of consciousness": she reports a sequence of thoughts and feelings that can divided in: : general attitude about life, memories of her past, and trivial moments and problems for the next day.
The scene is set in her bed: she is asleep and she is made up thoughts and sensation that follow one another in her mind creating a river-like flow. Her thoughts, apparently at random, do have a form: they begin with the word "yes" and end with the word "yes": so her thoughts flow in a circle, symbol of Molly, symbol of perfection: she becomes the quintessence of origin of men's experience: all the man she has known become one man.