A trick question. Richard Sears,Thomas Edison, and Andrew Carnegie were all telegraph operators. It was the "cool" job of the day.
Richard Sears was a telegraph operator and railroad station manager when he first experimented with selling pocket watches by mail order.
Andrew Carnegie was a telegrapher in Lincoln's office during the Civil War.
Edison's first profitable invention was a device called the Universal Stock Ticker, a telegraph-based stock quotation device. By the way, when this story runs in Wired, they'll probably make the graphic look like this.
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