Some towns have only one.
一些小镇中的交通信号灯只有一个灯。
Some have one every few feet.
有些地方每个几英尺就有一个。
Their three eyes looked down on passing vehicles, giving silent commands that millions follow daily.
他们的三个眼睛监督着过往车辆，每天给上百万车辆发出无声的指令。
This is the history of the traffic light.
这就是红绿灯的历史。
To explore the origins of the traffic light, we must first venture to London in 1866, a time when 1,102 people were killed and 1,134 injured on city roadways.
要找出红绿灯的起源，就要先说说1866年伦敦道路的一场事故，造成1102人死亡，1134人受伤。
A man by the name of John Peek Knight devised a manual gas-powered color lighting system to help regulate horse-drawn traffic.
一个名叫约翰·皮克·奈特的人设计了手动煤气红绿灯，来控制马车行驶的车道。
That system was based on railroad signals, using the colors red first stopped in green for go.
该系统以铁路信号灯为基础，首次使用“红灯停、绿灯行”来控制交通。
On December 9th,1868, the world's first traffic signal was installed near Westminster Bridge at the corners of Great George and Brige streets.
1868年12月9日，首个交通信号灯安装在了威斯敏斯特大桥附近，位于乔治街和布里奇街的拐角处。
Before this time traffic was directed by police officers using hand signals.
在此之前，道路上的交通都是警察用手势指挥的。
With this new color lighting system, carriage drivers and pedestrians could better see the traffic flow.
有了这一个交通信号灯系统，马车司机和行人都能更清楚的看见车流。
Unfortunately, only a few months after the traffic lights installation, a gas leak caused one of the lights to explode, severely injuring the police officer operating the device.
不幸的是，就在几个月后，煤气泄露引发其中一个信号灯爆炸，其中一个正在执勤的警察受重伤。
Due to this incident the new traffic system fell out of public favour.
也正因如此，新的交通系统失去了民心。
Well, this looked to be the end of the traffic light.
这似乎就是信号灯的结局了。
The device made a surprising return in 1912. With the popularity of the automobile over the horse-drawn carriage on the rise, more and more traffic accidents occurred all over the world.
但它在1912年意外回归。随着汽车的普及、马车的兴起，世界各地发生了越来越多的交通事故。
Drivers needed help.
司机们需要帮助。
So new traffic signals emerged in various forms.
因此新的交通信号灯以各种形式出现。
Lester Wire, a policeman in Salt Lake City, Utah created the electric form of the traffic signal.
在犹他州盐湖城，一位名叫莱斯特的警察发明了使用电力的红绿灯。
This version of the stop light designed in 1914 by James Hogue, included a buzzer to provide a warning for color changes as an added bonus fire stations and police could control the devices in case of an emergency.
这一款信号灯是由詹姆斯·霍格在1914年改进的，增加了蜂鸣器，可在灯切换之前发出警告。另外，消防局和警察局可在紧急情况下控制设备。
These new innovations paved the way for the modern traffic light that we know today.
这一项创举也为我们如今所知的现代交通信号灯打下了基础。
By 1922 many traffic signals were being automated on timers.
到1922年，许多交通信号灯有了倒计时。
American inventor Garrett Morgan witnessed a very serious accident between an automobile and horse-drawn carriage on a street corner in Cincinnati Ohio.
美国发明家加勒特·摩根在俄亥俄州辛辛那提的一个街角目睹了一辆汽车和马车之间的严重事故。
Inspired to prevent further accidents like that from happening, the inventor filed a US patent and changed the world.
为了避免这样的悲剧再次发生，他申请了美国专利并改变了世界。
Morgan's version had three light positions instead of just two.
摩根的设计由两个灯变成了三个灯。
Red, amber and green.
红色、黄色和绿色。
The middle position as we know today being yellow allowed for traffic to be warned that a stop was coming.
我们现在都知道，中间的黄灯主要是用来提醒人们即将变红灯了。
This greatly reduced the risk of a traffic incident in overtime.
这大大减少了高峰时期的交通事故风险。
Morgan's three-position signal took shape into the traffic lights we see today.
摩根的三色信号灯逐渐演变成了我们如今看到的红绿灯。
Currently modern traffic lights are completely computerized.
现代交通信号灯已完全电脑化了。
This became possible in the 1950s due to pressure plates being placed at intersections.
在二十世纪五十年代，压力板安置在十字路口。
Once a car was on a plate, computers would register the vehicle waiting at the light.
一旦汽车压到压力感应板，电脑就会记录下在信号灯前等待的车辆。
Such advances allowed for better traffic flow during rush hour and safer intersections for pedestrians.
这种技术的进步可以保证在高峰期间车流下，行人安全地通过马路。
Toronto Ontario was the first city to completely computerize its entire traffic signal systems by 1963. So the next time you see that red glow telling you to stop.
1963 年，安大略省多伦多市成为第一个完成全市交通信号系统电脑化的城市。所以下次当你看到红灯亮起，让你停下时。
Realize just how much went into making you safe in your vehicle.
想想为了保证你的行驶安全，付出了多少努力。
听友232530172
打卡