Though his formal schooling was limited to just three months of instruction before he was ten years old, Edison was one of the most prolific inventors of his time. His work in improving telegraph technology—particularly his discovery of a method for recording telegraph messages—led Edison to suspect he could do similar things with sound. Within months, the first working model of his phonograph was ready. Why, according to Edison, was he “taken aback” when his invention worked on the first try? Discuss
Source: The Free Dictionary