We are all acquainted with the yellow warning signs along Michigan’s roads alerting us to dangerous intersections, sharp curves, steep grades and other driving hazards. But few people are familiar with the devices that preceded these modern diamond-shaped caution notices, an old-time apparatus called the “highway lighthouse.”
These contraptions were invented around 1920 to alert vehicle operators to pending perils. Their method of conveying this message was by means of an intense flashing light. By positioning these blinking illuminators a hundred feet or so before a particular menace, motorists could prepare to take defensive action.
Highway lighthouses were nearly eight feet tall, shaped somewhat like an oversized antique gas pump and were fitted with a large lens in the middle of a top-mounted globe or drum. Through this round optics piece the warning signals were flashed by igniting pulses of acetylene gas.
These winking roadside markers were introduced to Michigan in 1921, transmitting cautionary tidings on state trunk lines and main county highways. The lighthouses served their purpose well, but were phased out beginning in 1927 with the introduction of uniform signage along the state’s ground transportation network.
By 1930 these stationary guide lamps had disappeared from the state. Today, not a museum in the country can be found possessing one of these illuminators from yesteryear.
For more great stories on Michigan’s past, look to Michigan History magazine. For more information or a free trial issue, call (800) 366-3703 or visit http://www.michiganhistorymagazine.com/.