Warning and Communication Devices
The traditional warning device on trams is a large gong (not unlike the gongs used to start and stop boxing fights). Tram gongs were pulsed by depressing a foot pedal, with the gong located directly below the pedal, under the floor. In some later trams the gong was operated by air pressure, again activated by depressing a floor pedal or by pushing a console button. In some areas, particularly in Europe an electric bell was employed, controlled by floor pedal or console button, these bells would ring continuously with the button/pedal depressed and thus were not unlike alarm bells.
Many modern trams in both Melbourne and many European cities – especially low floored models – use an amplified, digital recording of a tram gong, rather than an actual gong under the tram, with the use of a supplementary horn common.
An additional means of communication are the conductor's bells. These are smaller bells, or buzzers, usually ceiling or wall mounted, located above or beside the motorman. They were either operated by the conductor pulling a leather or rope cord which ran the length of the tram, or in the case of electric buzzers, operated by the conductor pressing a button in the passenger cabin (or rarely on the outside of the tram). In some systems passengers were allowed to ring the conductor's bell to let the driver know that they wanted to be let off at the next stop. Drivers could also communicate to the conductor using the bells.
The number of times the conductor's bell was rung would indicate what was required to be done. The following is a typical code as operated in Brisbane Australia:
conductor to motorman -
- one ring - stop at next stop
- two rings - all clear, driver may proceed
- three rings - emergency stop
- four rings - tram is full, do not stop to pick up additional passengers
motorman to conductor -
- one ring - release the hand brake
- two rings - I have control of the hand brake
- three rings - emergency stop
- four rings - come here
Read more about this topic: Tram Controls
Famous quotes containing the words warning and, warning and/or devices:
“They learned to rattle the lock and key
To give whatever might chance to be,
Warning and time to be off in flight:”
—Robert Frost (1874–1963)
“What I am now warning the People of is, That the News-Papers of this Island are as pernicious to weak Heads in England as ever Books of Chivalry to Spain; and therefore shall do all that in me lies, with the utmost Care and Vigilance imaginable, to prevent these growing Evils.”
—Richard Steele (1672–1729)
“Soon silence will have passed into legend. Man has turned his back on silence. Day after day he invents machines and devices that increase noise and distract humanity from the essence of life, contemplation, meditation.... Tooting, howling, screeching, booming, crashing, whistling, grinding, and trilling bolster his ego. His anxiety subsides. His inhuman void spreads monstrously like a gray vegetation.”
—Jean Arp (1887–1948)