Thomas Edison: The Birth of Recorded Sound

This post is by Amara Alexander, the 2019-20 Albert Einstein Distinguished Educator Fellow at the Library of Congress.

While I’m preparing for a lesson or teaching a group of students, music is often playing in the background. Those sounds were recorded on one device and are being played back on another. A variety of tools are available today to record and play back sound; however, the first premiered in 1887.

Thomas Edison, an American inventor from New Jersey, invented the first device to record and play back sound. The phonograph was the predecessor of present-day recording machines. Taken in 1892, this image captures the early development of the phonograph in Edison’s laboratory. Present the photograph to students, and then stimulate their thinking with questions such as:

• What do you notice about the image?
• What questions do you have about the image?
• Who might use the items in the image?
• Why was the image captured?

Use the Observe-Reflect-Question analysis tool to help students record their thinking about the image. After they’ve analyzed the image, focus their thinking by asking: What do they think is the purpose for the device shown in the photograph? What details from the image support their hypotheses?

Build upon student’s responses to introduce them to the engineering design process. Edison sketched his design, worked with an assistant to create it, tested the phonograph, and improved upon his invention for years. Using a graphic organizer, support students in identifying Edison’s design process for the phonograph. The Thomas Edison, Electricity and America lesson plan is another resource for teachers and students to investigate Edison’s role as an inventor in the advancement of technologies.

Extensions to engage students:

• Showcase different images of recording machines beginning with the phonograph to present-day technologies;
• Pair an image of a modern recording device with the phonograph and direct students to compare and contrast;
• Challenge students to improve Edison’s phonograph;
• Bridge the establishment of recorded sound to sound waves.

How can you use Edison’s invention to teach the engineering design process? What might be other methods to inform students of Thomas Edison’s inventions and the relationship between modern technologies?