Equal Rites, the third installment in the Discworld series, centers not around Rincewind, who's probably still recuperating from the events of The Light Fantastic, but around Granny Weatherwax, a happy-to-be-rural witch. Weatherwax becomes the unwilling guardian of Esk, the eighth child of an eighth son, after a rapidly expiring wizard passed along his powers and staff to the infant without bothering to check its gender. Esk, of course, is a girl.

In the gender-separations of the Discworld, wizard (air) magic is for men and witch (earth) magic is for women. But as Esk grows, she manifests signs of wizard power. Granny Weatherwax tries to block that eventuality by training the young girl in the witchery arts -- a kinder, gentler magic all around, without all the pyrotechnical trappings of wizardry.

But Weatherwax eventually must concede that Esk's innate wizard's skills are too great -- and that Esk is at risk of burning down the landscape. And so the two reluctantly set off to find the Unseen University, where wizards are trained and women are forbidden, in the great city of Ankh-Morpork. Of course they get separated along the way and have various adventures with barges, caravans and brooms before meeting up again en route to the city.

Along the way, Esk meets various helpful and unhelpful people, including an apprentice wizard with raw genius for his work despite an unfortunate allergy to everything. Once they arrive in Ankh-Morpork and are laughed out of the university for being female, the two connive to do what they can to get Esk some training anyway.

It doesn't hurt that, at age almost-9, Esk already has a great deal more power than many of her snooty elders.

Equal Rites is a grand addition to the Discworld tradition, and introduces characters who will play more important roles later in the series. If one scene seems borrowed rather heavily from a well-known battle between Merlin and Madam Mim -- well, it made me chuckle, anyway.