7:15 AM | *84 years later and the tornado scene in the “Wizard of Oz” is still a classic* — Arcfield Weather

The makings of a classic tornado scene

As far as the tornado scene is concerned, it is still regarded as incredibly realistic – even in today’s era of computer-generated special effects. The first attempt at a tornado by the movie’s special effects director, Arnold Gillespie, was to use a 35-foot tall rubber cone, but this turned out to be too rigid and simply wouldn’t move. Next, the special effects director recalled from his experience as a pilot (even had his own airplane) that wind socks at airports had the classic funnel-shape of a tornado. He decided to make a tornado out of muslin (plane woven cloth) which would allow it to twist, bend and move from side-to-side. He built a 35-foot long tapered muslin sock and connected the top of it to a steel gantry suspended at 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 sock disappeared into a slot on the stage floor where it connected to a rod which came up through the base of the tornado to pull it from side-to-side. By moving the gantry and rod in different directions, the tornado appeared to “snake” across the stage.

To produce the dust and debris that makes a real tornado visible, they used compressed air hoses to spray a powdery brown dust known as “Fullers Earth” from both the top and bottom of the funnel. The muslin sock was sufficiently porous that some of the dust sifted through giving a blur or softness to the material and a fuzziness to the edges 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 gray balls of cotton (great for mammatus clouds) 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 sulfur 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.

An interesting feature about the tornado scene is that the farmhouse, fence, barn and prairie were all done in miniature. In the first part of the scene where Dorothy is running home to Aunty “Em” after visiting the traveling medicine man, there is 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 miniatures scaled at three quarters of an inch to the foot (Source: AmericaBlog).  The house was not more than three feet high and adjacent cornfields were about three inches tall!