A century ago, when these towers were gaining popularity, the lookouts used telephones, heliographs and carrier pigeons to notify others of fires. A telephone plugs into the wall and transmits electrical impulses that translate into voice. A heliograph is a mirror that reflects coded flashes of sunlight, usually using Morse code. A pigeon is a pigeon. In the latter part of the 20th century, fire towers had mostly been phased out due to declining budgets and new, more advanced technologies. And still, towers remain standing — some of us believe that the human eye is the best surveillance tool available, better than cell phones, aircraft, GPS, radio technology and satellite imaging.