II.

Early Inventions

Edison acquired his knowledge of electricity and telegraphy (use of a telegraph system to communicate at a distance) as a teenager. In 1868, at age 21, he developed a telegraphic vote-recording machine, the first of his inventions to be patented. The next year, Edison invented an improved version of the stock ticker, which printed stock market quotations and gold prices on a paper tape. Unlike older stock tickers, Edison's was fully automatic, and it did away with the need for a special attendant to operate each machine.

These early inventions brought Edison no financial returns. The first invention to bring him money was another improvement on the stock ticker. Edison created a central mechanism by which all the receiving tickers could be put in unison with the main sending apparatus. For this invention, Edison received $40,000, which would be worth $530,000 in 2000. He and a business partner, who operated a machine shop, used the money to start a new company to manufacture Edison’s improved stock ticker. For the next five years Edison spent up to 18 hours a day in his workshop in Newark, New Jersey, inventing and manufacturing a variety of electrical devices. One important device that he designed during this period was the quadruplex, a highly efficient telegraph that could send four messages at a time over a telegraph wire, instead of just one.