Adler Alternate Flashing Relay

Description
Automobile traffic increased significantly in the early 20th century, and so did collisions between cars and trains. Railroad companies installed warning signs and bells at crossings, but drivers ignored the signs, and motor noise drowned out the bells. Charles Adler, Jr., an inventor of traffic safety devices, tried signs that moved to attract the driver's attention. His 1921 STOP signal turned toward motorists when a train was approaching. In 1922, the Association of American Railroads chose a different signal—a pair of alternating flashing red lights—as the national standard. Adler devised a relay to create the alternating light pattern, and it was used by more than 40 railroads.
Location
Currently on loan
Object Name
flashing relay
date made
1920s
ID Number
1989.0745.41
accession number
1989.0745
catalog number
1989.0745.41
subject
Transportation
Road Transportation
See more items in
Work and Industry: Transportation, Road
Road Transportation
Data Source
National Museum of American History, Kenneth E. Behring Center

Visitor Comments

Add a comment about this object

**Please read before submitting the form**

Have a comment or question about this object to share with the community? Please use the form below. Selected comments will appear on this page and may receive a museum response (but we can't promise). Please note that we generally cannot answer questions about the history, rarity, or value of your personal artifacts.

Have a question about anything else, or would you prefer a personal response? Please visit our FAQ or contact page.

Personal information will not be shared or result in unsolicited e-mail. See our privacy policy.

Image CAPTCHA
Enter the characters shown in the image.