Another improvement , by the famed inventor thomas alva edison ( 1847-1931 ) in 1874 , was the quadruplex system , which allowed for four messages to be transmitted simultaneously using the same wire .

另一项技术进步四路系统，由著名发明家托马斯阿尔瓦爱迪生（thomasalvaedison，1847-1931）于1874年发明，它可以使四条信息在同一条电报线上同时传送。