The first in Baum’s oeuvre was Maetta, a Glinda-like character in A New Wonderland, completed in the mid-1890s and finally published in early 1900. Three years later that book was republished as The Magical Monarch of Mo. The second sorceress was Gayelette, who created the Golden Cap that enslaved the Winged Monkeys at some unspecified time before the Wizard’s arrival in Oz.
The Wonderful Wizard of Oz mentions sorceresses elsewhere as well. The Good Witch of the North says, “In the civilized countries I believe there are no witches left, nor wizards, nor sorceresses, nor magicians.” The Munchkins keep calling Dorothy a sorceress because she’s killed the Witch of the East and taken her shoes, and because she wears white: “only witches and sorceresses wear white.”
Those statements suggest that “witch” and “sorceress” are similar, overlapping categories. But then there’s this remark early in The Marvelous Land of Oz:
Mombi was not exactly a Witch, because the Good Witch who ruled that part of the Land of Oz had forbidden any other Witch to exist in her dominions. So [she], however much she might aspire to working magic, realized it was unlawful to be more than a Sorceress, or at most a Wizardess.That implies that a Wizardess was somehow superior to a Sorceress, and both inferior to a Witch.
However, later in that same book Glinda herself suggests that a major difference between a Sorceress and a Witch involves the type of magic each does:
“Really,” said the Sorceress, “that is beyond my magic. I never deal in transformations, for they are not honest, and no respectable sorceress likes to make things appear to be what they are not. Only unscrupulous witches use the art…”That said, in Rinkitink in Oz (1916), Glinda disenchants a character without discussing such scruples. So it’s not that she can’t do transformations as a sorceress; with Mombi available to reverse her own spell, Glinda chooses not to.
Baum often has characters discuss different types of magic, as in Ozma’s remark to Dorothy in his last book, Glinda of Oz (published 1920):
“I am a more powerful fairy than any other inhabitant of Oz, I am not as powerful as Glinda the Sorceress, who has studied many arts of magic that I know nothing of. Even the little Wizard of Oz can do some things I am unable to accomplish, while I can accomplish things unknown to the Wizard. This is to explain that I’m not all-powerful, by any means. My magic is simply fairy magic, and not sorcery or wizardry.”That novel also introduces a “krumbic witch,” who esoteric spells baffle even Glinda, and offers our second view of a “yookoohoo,” a magician who specializes in transformations.
Baum was not a consistent writer, and he never laid out all his different forms of magic and which type of magician was more powerful than another. If he had done so, he might well have contradicted that system a few books later when he had a better idea.
But one thing Baum was consistent about was that Glinda is the most powerful magician in Oz. That might imply that a Sorceress is more powerful than a Witch, but perhaps that particular Sorceress is simply more powerful than any Witch. In any event, if Glinda wants to call herself a Sorceress, not many people would dare to object.