THE OZ TORNADO
by Tim Marshall
© Copyright Tim Marshall
Like many of you, I was inspired by the movie The Wizard of Oz as a child and have always liked the tornado scene. The tornado looks so real as it snakes back and forth churning up the Kansas corn fields. Since 1938, when the film was made, there has never been a "man-made" tornado in a movie that has looked so real. I have often wondered how this tornado was constructed and filmed. My research into this subject led me to a book entitled: The Making of the Wizard of Oz written by Aljean HarmetzO The book has provided me with an absolutely fascinating account of how the tornado was constructed.
Movie giant MGM initially budgeted S8,000 to design, build, and photograph the first tornado. It was a thirty-five foot tall rubber cone. The problem was the tornado was too rigid and wouldn't move. It just hung there. Special effects coordinator and inventor Arnold Gillespie simply tore down the rubber tornado and tried again. Gillespie didn't know much about tornadoes but realized he couldn't go to Kansas and wait for a tornado to come down and pick up a house. So, he relied upon his background as a pilot for many years (even had his own airplane) for his next idea. He remembered that wind socks at airports resembled the shape of a tornado. He decided to make a tornado out of muslin (plain woven cloth) keeping it flexible so that it could bend, twist, and move from side to side.
Gillespie finally built a thirty-five foot long tapered muslin sock. The top of the tornado was connected to a steel gantry suspended from the top of the stage. The gantry alone cost more than $12,000 (in 1938 dollars) and was specifically built for the tornado by Bethlehem Steel. It was a mobile structure similar to those used in warehouses to lift heavy objects and could travel the entire length of the stage. The bottom of the tornado disappeared into a slot in the stage floor. A rod came up through the base of the tornado to pull it from one side to another. By moving the gantry and the rod in opposite directions, it would make the tornado appear to snake back and forth.
The first muslin tornado moved too violently and tore loose at the bottom. It was decided to mend the fabric with music wire so it would hold together when spun. This was a tedious task as one person had to be inside the tornado to poke the needle back out each time. To heighten the illusion a product known as "fullers earth", a powdery brown dust, was sprayed into the base of the tornado with hoses containing compressed air. The same material also was sprayed into the top of the wind sock. The result was a boiling mass of dirt or cloud. The muslin was sufficiently porous that some of the dirt sifted through giving a blur or softness to the material. This also kept the the sides of the tornado fuzzy, so that it didn't look like a hard surface.
Four or five feet in front of the cameras were two panels of glass on which grey balls of cotton (great for mammatus) had been pasted. The two panels moved in opposite directions adding to the boiling sensation and, at the same time, they obscured the steel gantry and top portion of the tornado. Dense clouds of yellow-black smoke made from sulfer and carbon were injected onto the set from a catwalk above the gantry. The stage hands had no respirators and stayed up there breathing the stuff until they couldn't stand it. Many of them became ill and some coughed up black-yellow mucous even days after the tornado was photographed. There was no OSHA in those days.
Once the tornado had been filmed, there was still plenty of work to be done. Rear- projection was used to transfer the previously shot tornado image onto a translucent screen while actors such as Dorothy were placed in front of it. Wind machines provided the big blow while stage hands threw dried leaves and other debris in the air. When the tornado came real close to the house at the end of the scene, more debris and dirt were added in the foreground to obscure the fake tornado while providing more realism. The tornado scene in the Wizard of Oz ended up costing more money than any other special effect in the movie.
Remember the first scene where Dorothy was running home to Aunty Em after visiting the traveling medicine man? There was a fence in the foreground and she hurries to open it as the tornado appears in the background. Dorothy's house can be seen in the background with the barn to the right. These structures were actually minatures scaled at three quarter of an inch to the foot. The house was not more than three feet high and adjacent cornfields were about three inches tall! The tornado swayed back and forth as fullers earth, carbon, and sulfer drift downward appearing like bursts of rain. Of course, the loud wind sound really makes this scene too!
As Dorothy ran to the tornado cellar at the back of the house, the tornado bent and swept to the right over the three inch tall corn stalks. Fullers earth was shot up the base of the tornado making it appear that the ground was being dug up. Dorothy retreated to her bedroom only to be struck in the back of the head by a window frame. (Most injuries in tornadoes are from flying debris.) As Dorothy dreamed that her house was lofted into the air whirling inside the tornado, the cameras were simply taken off their tripods and moved around giving the viewer a floating sensation.
Then Dorothy awakened and looked outside her window. She saw the spinning tornado, and peered downward towards its base. This was again reverse projection through a translucent screen from tornado images shot earlier. The camera was actually put inside the wind sock and rotated while the sock remained stationary! This was much easier than trying to rotate a baggy wind sock with an expensive camera inside. Some dark stripes were painted on the muslin inside the tornado and a little dust was added to give the incredible whirling effect.
White images floating by Dorothy's window were actually double-images that were cast on a transulcent screen through reverse projection. The crate of chickens, two men in the rowboat, old lady in the rocking chair, and school teacher (who could forget "Miss Gulch") on her bicycle who turns into a witch on a broomstick were all filmed against a neutral background and then projected onto a film of the tornado. In essence, this was a film of a film. So Dorothy really saw a transulcent screen with the double images projected upon it.
I hope this little article doesn't ruin the film for you next time you watch it. If you are like me, you will still be amazed at how real this was, all done with muslin cloth and dust back in 1938. Many people still believe this was a real tornado projected onto a screen. Sorry, but that's Hollywood folks!