The Acme and Other Vintage Traffic Signals - City of Los Angeles

The Acme and Other Vintage Traffic Signals 

Manually-operated traffic signals first appeared in Salt Lake City in 1912, then in 

Cleveland in 1914, followed by San Francisco (1915) and Baltimore (1916). However, 

the most extensive experimentation with a variety of vintage (pre-tri-light) traffic signals 

occurred in Southern California. 

In 1917, Frank J. Husbands of Los Angeles received a patent (No. 1,236,441) for what 

would later be known as the Acme Traffic Signal. In October 1920 in Los Angeles, 

experimental automated Acme signals, with red and green lights, “Stop” and “Go” 

semaphore arms and bells, were installed at five locations along Broadway between 3 rd 

and 7 th Streets. The experiment was successful and by 1923, there were 31 of these 

signals, all interconnected, throughout the Central Business District. It was the most 

advanced signal system in the world at that time. It was adopted as the City’s standard 

signal in 1924. 

Meanwhile, between 1921 and 1924, the City of Los Angeles experimented with other 

vintage traffic signals. Also, between 1928 and 1931, nearby jurisdictions experimented 

with other novel traffic signals that were invented, patented and deployed, each on a 

limited basis. Manufacturers of these devices included Griswold (American Bobby), 

General Electric (Novalux), Adco, Waterhouse and one by the Automobile Club of 

Southern California. A traffic signal with foldable arms was patented by Garrett A. 

Morgan in 1923. However, he sold his rights of his invention to General Electric and his 

device was not deployed. Like the Acme, these experimental traffic signals usually 

featured bells, mechanical rotation to display “Stop” and “Go”messages and placement 

either in the middle of the intersection or in the near-right position. 

Of all the vintage traffic signals, the Acme certainly was the most interesting. It was the 

most animated of all the signals and appealed to the senses through red and green 

colors, Stop and Go messages, bell sounds a vertical rotation motion. Also, it was the 

first manufactured automated traffic signal to be widely deployed. Although it was a 

defining feature for the City of Angels, it was used in other cities in Southern California 

and saw application at various locations throughout the nation. Over 800 intersections 

ultimately would be equipped with the Acme in Los Angeles, more than any other 

vintage signal. 

Several noteworthy breakthroughs in traffic control were achieved using the Acme. 

Through the use of a combination of factors, including the pioneering 1925 Jaywalking 

Ordinance, short cycle lengths and the animation and sounds of the Acme, pedestrian 

were effectively regulated for the first time in a major city in 1925. In 1926, Dorsey, after 

extensive experimentation with offsets and cycle lengths, operated 16 time-of-day/dayof-week 

plans from a central control station and developed the “half alternating” offset 

concept to minimize delay in a central business district network. In 1928, railroad preemption 

features were first applied by Dorsey. On January 14, 1929, Dorsey installed

the world first pedestrian activated (push button) signal as a school safety measure at 

the intersection of Figueroa Street and Meridian Avenue. 

But the honeymoon period for the Acme wouldn’t last forever. In October 1920, William 

Potts of Detroit invented and installed the first tri-light traffic signal. In 1922, a 

manufactured version of the tri-light signal was installed in Syracuse, New York. By the 

latter half of the 1920s, major cities that had been relying on traffic officers, signal 

towers and manual traffic signals decided to deploy automated traffic signals. By this 

time, several manufactured tri-light signals became available and worked well. At the 

same time, there was a backlash against the noisy bell sounds as the Acme began to 

be installed beyond the central business district near residential areas. In addition, the 

constant mechanical motion of the semaphore arms eventually resulted in their being 

stuck and out of sync with the bells and lights. (The lack of an explicit clearance interval 

wasn’t a large concern, as seven second all-red intervals were provided.) The 

newspaper and civic leaders took notice of the tri-light signals in other large cities and 

began a campaign to replace the Acmes. Miller McClintock was hired to prepare a 

traffic control plan for fashionable Wilshire Boulevard and, to no one’s surprise, 

recommended tri-light signals. Decorative Eagle signals replaced the Acmes on 

Wilshire Boulevard in September 1931, and no other Acmes were installed in the City 

after that time. The Acme survived until December 1956, when the last one was 

removed. 

But the Acme lives on! One surviving and operable Acme is retained by the Department 

of Transportation. Another is on display at the Smithsonian in Washington, D.C. Three 

Acmes are located at the Orange Empire Trolley Museum in Perris, California, and a 

few are held by collectors. Period movies use replicated Acme signals to represent Los 

Angeles in the 1930s and 1940s, such as “Who Framed Roger Rabbit” and “Devil in a 

Blue Dress”. Finally, the MGM/Disney Theme Park in Orlando, Florida immortalizes the 

Hollywood and Wilshire Districts by replicating nostalgic scenes and art deco buildings 

from the 1930s. At the intersections in this miniature city setting, they included Acme 

traffic signals to put the finishing touches on the theme. 

C:\Documents and Settings\JANET E\My Documents\Historical\Trans Topics & Tales (in Word docs)\Acme and Other Vintage Traffic Signals.doc

The original Acme signal contract for the City of Los 

Angeles 

Graphic - 3138 

The second Acme signal style, circa 1926, on Wilshire 

Boulevard at Western Avenue 


The first Acme signal style, circa 1924 


The primary Acme style, circa 1928 

Graphic - 2042

Acme signal plan 


Ceremony for removal of the last Acme signal on Main 

Street at Sunset Boulevard, December 1956 


Acme signal bells 


Acme timing chart 

Graphic - 1024

Acme cartoon, illustrating signal birds 


Anti-Acme editorial cartoon 





Graphic - 3066



“Waterhouse”, the vintage signal of the 

County of Los Angeles on Santa Monica 

Boulevard at La Brea Avenue 


“American Bobby” signal at Wilshire Boulevard and 

Western Avenue, looking north, circa 1925 


Adco signal on Washington Boulevard at MGM 

Studios 

Graphic - 3084

Auto Club signal at Adams Boulevard and Figueroa Street 

Graphic - 8042

The Acme and Other Vintage Traffic Signals - City of Los Angeles

Create successful ePaper yourself

Delete template?

Save as template?