The Silver Chair is, chronologically, the penultimate volume in The Chronicles of Narnia, and its tone is darker than any of the other novels in the series.
C.S. Lewis recalls the character Eustace Scrubb back to Narnia, and introduces a new heroine in Jill Pole, Eustace’s classmate. It is notable that recognizable characters from previous volumes are very limited; the author invented many new characters for this novel. The setting of the Wild Lands of the North constitutes a new addition to the geography of Narnia. The Marsh-wiggle, Puddleglum, has an interesting disposition with absolute pessimism masking a strong, valiant spirit and moral integrity. He steadies Eustace and Jill as their guide and companion on their journey to find the lost son of King Caspian, Prince Rilian. This is the quest commanded by Aslan and for which both children were summoned from the real world.
The lapse in time between Narnia and the real world is intriguing, as all novels in the series have varying answers to that issue. The creation of a new antagonist similar to the White Witch is the Lady of the Green Kirtle, a witch herself and the captor of Prince Rilian. The Underland is described like the underworlds of Greek and Roman mythology, with the exception that the Underland is not the land of the dead but the kingdom of the Lady of the Green Kirtle. The storyline itself has traits in common with the myth of Orpheus and Eurydice. It is impossible to not see that the green serpent is a symbol of Satan. The silver chair indicated by the title is an object of mystery never fully explained by Lewis except it being an evil tool of the Lady of the Green Kirtle. Serious, reflective, and surprisingly entertaining, The Silver Chair focuses on the importance of the four cardinal virtues while advancing the entire narrative concerning the world of Narnia to its next and final chronicle.
Part 6: ‘The Chronicles of Narnia’ by C.S. Lewis, Examiner.com