Locomotive:
There are five main elements to Hart Benton's mural, "Instruments of Power" (1930). The locomotive in this image is shown, like the other two transportation elements, in motion.

Aircraft:
The airplane shown in the top left section of this image celebrates the achievements of aviators such as Charles A. Lindbergh who crossed the Atlantic on May 21, 1927.
To learn more click here: The Aviation History Online Museum

Blimp:
The airship in this image was a common sight in the sky during the 1930s and represented an elegant, technologically advanced form of travel. Following the explosion of the Hindenberg on May 6, 1937, rigid airships ceased to be icon of technological sophistication and progress.

Hydroelectric Power:
The hydroelectric facility shown in the bottom of this image depicts a cheap, sustainable, carefully engineered power source. It is shown, along with the other technologies in this image, as an example of a modern, rational, engineering achievement.

Engine:
The engine shown in the center of this image combines elements from a number of different engine designs and is intended to express the forces driving the development of the technology itself.