section_path: Other inventions and projects/Telegraph improvements
section_name: Telegraph improvements
paragraph_text: Telegraph improvements
  
  The key to Edison's initial reputation and success was his work in the field of telegraphy. With knowledge gained from years of working as a telegraph operator, he learned the basics of electricity. This, together with his studies in chemistry at the Cooper Union, allowed him to make his early fortune with the stock ticker, the first electricity-based broadcast system. His innovations also included the development of the quadruplex, the first system which could simultaneously transmit four messages through a single wire.