In "The Praise of Chimney Sweepers," Elia says that he thinks little of people's teeth but is always fascinated when a chimney sweep flashes his teeth from behind a sooty face. Here, the white teeth symbolize something essential and special to the character of these boys that Lamb sees—a kind of purity that might register as paradoxical given their filthy work.
The Dream Children (Allegory)
In "Dream-Children; A Reverie," Elia recounts stories of his family to his children, who vanish when he starts talking about their mother. The account is a kind of allegory for loneliness, as Elia's children literally disappear from him when he begins to remember that his chance at having a wife and kids was lost. Only in a dream does Elia have children to regale with stories, and in life, he has just himself.
John Milton, writer of the English epic poem Paradise Lost, appears again and again in Lamb's essays. Sometimes, Lamb simply references him as an important, brilliant writer, but at other points, Lamb quotes Milton. As a fellow poet who had his own unique ideas about Christianity and worship, Milton could he seen as appearing in Lamb's essays as a kind of validation of Lamb's own background and perspectives.
The Tea Ceremony (Allegory)
When Elia looks into a tea cup in "Old China" and sees a tea ceremony play out, he is outlining a kind of idealized conversational interaction which is quickly countered by the conversation that he has with Cousin Bridget about their less privileged past. Like with many of the allegories that Lamb employs, the point of them is not so much the subject matter as how they provide a stark contrast with his actual life. This allegory, like the one in "Dream-Children; A Reverie" provides a kind of negative example of what is unlike the life Charles Lamb knew.
The New Year's Festival (Allegory)
The entirety of "Rejoicings Upon the New Year's Coming of Age" is essentially an allegory, as the personality embodied by each of the days of the year is supposed to reflect what those days is actually like. April Fool's Day is mischievous but brings everyone together, while Ash Wednesday is laborious and terribly self-serious. The fun of the allegory is partially seeing how these days play with each other, but also to learn a bit about Lamb's own conception of time.
Charles Lamb: Essays Questions and Answers
The Question and Answer section for Charles Lamb: Essays is a great
resource to ask questions, find answers, and discuss the novel.