174:
53:
The old system of police directing traffic had become increasingly outmoded; two-color signals, with green and red lights, already existed, but they did not leave drivers sufficient time to stop at high speeds. Some municipalities experimented with leaving the green on for a few seconds after the red
54:
was illuminated, to caution the driver that the right of way was soon to change. In 1917, Potts devised a new system by inventing a "yellow" or "amber" light which would shine after the green light and before the red light to indicate the impending transition.
49:
lists Potts as 17 years old and a police officer. By 1910, he was married to Grace (Baker) Potts, and they subsequently had 4 children. Potts became the "superintendent, signal person police" for the city of
Detroit.
57:
In 1920, Potts designed the first four-way, three-color traffic signal tower, which was installed at the intersection of
Woodward and Michigan Avenues in Detroit, in October 1920.
240:
211:
255:
250:
76:
97:
260:
204:
46:
197:
245:
33:, though after a short test installation, traffic lights were not seen again in the U.K. until 1929.)
235:
230:
21:(May 1883 – 1947) was a Detroit police officer who is credited with inventing the modern, three-lens
134:
42:
29:
in 1920. (A gas-powered, two-lens, red/green traffic signal was invented in London in 1868 by
159:
181:
224:
71:
22:
180:
This article about a United States engineer, inventor or industrial designer is a
66:
30:
154:
26:
173:
160:
http://signalfan.freeservers.com/historical/pottssig1.htm
185:
205:
8:
212:
198:
88:
77:Traffic-light signalling and operation
7:
170:
168:
155:http://didyouknow.org/trafficlights/
98:"The man who gave us traffic lights"
241:Detroit Police Department officers
14:
172:
256:20th-century American inventors
1:
251:People from Bad Axe, Michigan
184:. You can help Knowledge by
277:
167:
125:. Bloomsbury, 2016, p. 71.
41:William Potts was born in
261:American engineer stubs
96:BBC (July 22, 2009).
193:
192:
31:John Peake Knight
268:
214:
207:
200:
176:
169:
142:
135:Mr. Trafficlight
132:
126:
121:Henry Petroski,
119:
113:
112:
110:
108:
93:
45:, Michigan. The
276:
275:
271:
270:
269:
267:
266:
265:
246:Traffic signals
221:
220:
219:
218:
165:
151:
146:
145:
133:
129:
120:
116:
106:
104:
95:
94:
90:
85:
63:
39:
12:
11:
5:
274:
272:
264:
263:
258:
253:
248:
243:
238:
233:
223:
222:
217:
216:
209:
202:
194:
191:
190:
177:
163:
162:
157:
150:
149:External links
147:
144:
143:
127:
123:The Road Taken
114:
87:
86:
84:
81:
80:
79:
74:
69:
62:
59:
38:
35:
13:
10:
9:
6:
4:
3:
2:
273:
262:
259:
257:
254:
252:
249:
247:
244:
242:
239:
237:
234:
232:
229:
228:
226:
215:
210:
208:
203:
201:
196:
195:
189:
187:
183:
178:
175:
171:
166:
161:
158:
156:
153:
152:
148:
141:, March 1947.
140:
136:
131:
128:
124:
118:
115:
103:
102:www.bbc.co.uk
99:
92:
89:
82:
78:
75:
73:
72:Traffic light
70:
68:
65:
64:
60:
58:
55:
51:
48:
44:
36:
34:
32:
28:
24:
23:traffic light
20:
19:William Potts
16:
186:expanding it
179:
164:
138:
130:
122:
117:
105:. Retrieved
101:
91:
56:
52:
40:
18:
17:
15:
236:1947 deaths
231:1883 births
67:Lester Wire
47:1900 census
225:Categories
139:Motor News
83:References
37:Biography
107:July 24,
61:See also
43:Bad Axe
27:Detroit
182:stub
109:2024
25:in
227::
137:.
100:.
213:e
206:t
199:v
188:.
111:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
