In 1950, the observatory ordered a grain silo from a Sears & Roebuck catalog and modified it to use as a telescope dome. Modifications included a slit in the roof and the ability to rotate in order to track the sun. Inside the dome was a 10-foot (3 m) spar where different telescopes could be mounted. The Grain Bin instrument was the first telescope installed at Sacramento Peak and only the second coronagraph station to be built in the Western hemisphere. Many high-quality motion-picture films of the sun's corona have been taken with this facility.