Friday is the 75th anniversary of the release of the Wizard of Oz, the first film to depict an authentic looking tornado with movie magic. Through the decades, the all time classic has inspired movie-goers and future meteorologists alike with scenes of a twister vaulting Dorothy’s home into the sky over her sleepy Kansas town.

In a tribute video (above) created by Penn State’s Department of Meteorology, Jon Nese recounts the history of the movie, which was based on the 1900 novel The Wonderful Wizard of Oz by L. Frank Baum.

Nese points out that Baum’s setting of rural Kansas was not a random choice. While working as editor of a newspaper in South Dakota, which was then the Dakota Territory, Baum came across the story of twin tornadoes that raked through Irving, Kan., destroying the town. He used that as inspiration to create the opening scenes of the beloved film.

(Related: In a Wizard of Oz-like twist, a house-like structure was lofted into the air when one of a pair of tornadoes swept through Pilger, Neb. earlier this year: Watch video.)

The exceptionally high production cost prevented the studio from recouping its investment until The Wizard of Oz was re-released a decade later. Part of the large expense was the production of the tornado scene itself. In the video, Nese describes how extraordinary the special effects were for its time:

Special effects director Arnold Gillespie knew he couldn’t go to Kansas and wait for a real tornado to pick up a house, so he first tried building a 35 foot tall rubber cone. That rubber tornado turned out to be too rigid. It wouldn’t move.
Next, Gillespie recalled that wind socks the ones that hung at airports, resembled a classic tornado funnel shape. He decided to make a tornado out of plain, woven, muslin cloth, which would allow it to twist, bend, and move from side to side. He connected the top of a 35 foot long tapered muslin sock to a steel gantry suspended at the top of the stage. The gantry alone cost more than what was budgeted for the entire tornado sequence.
The bottom of the tornado disappeared into a slot on the stage floor, where it connected to a rod. By moving the gantry and the rod in different directions, the tornado appeared to snake and wiggle its way across the stage. To produce the dust and debris that makes a real tornado visible, Gillespie used compressed air hoses to spray a powdery-brown dust, a product known as “Fullers Earth,” from both the top and bottom of the funnel. The muslin was porous enough that some of the dirt came through, giving the tornado a realistic looking fuzziness on the edges.
So essentially, the Wizard of Oz tornado was nothing but a large, tapered, cloth sock, with lots of wind and dirt thrown at it.

The Wizard of Oz was nominated for six Academy Awards, including best picture. However, despite the lovable characters and amazing tornado special effects, the film did not win that category. Instead, another blustery film won best picture that year — Gone with the Wind.