Wizard of Oz Fact

When I was trying to dissolve Wizard of Oz urban legends, I was surprised to find this fact at wikipedia. Gale Sondergaard was originally cast as The Wicked Witch of the West. Sondergaard had thought of the witch more as the Snow White Character, not someone who would be afraid of bathroom vanities. She left & the new witch was played by Margaret Hamilton .

Margaret was severely burned during the Munchkinland scene. She was supposed to disappear into a puff of fiery smoke. She was hospitalized & refused to fly on the broomstick when it billows smoke. The directors used a stand-in instead. The stand-in was also injured during the scene. I guess the Wizard of Oz people never learned their lesson the first time.