When Edison was twelve years old, he contracted scarlet fever. The effects of the fever, as well as getting picked up by the ears by a train conductor, caused Edison to become completely deaf in his left ear, and 80 percent deaf in the other. He learned Morse code of the telegraph, and began a job as a "brass pounder" (telegraph operator). At age sixteen, Edison made his first invention, which was called an "automatic repeater." It used punched tape to send telegraph signals quickly between unmanned stations, more quickly than a telegraph operator could do.