Not for Charles Adler Jr., though. Seven decades ago, his grand planning didn't stop when the light changed. Wearying even in those pregridlock days of his wait at timed stoplights, the young Baltimorean came up with the world's first traffic signal activated by the presence of waiting cars. The age of the "traffic-actuated signal" began Feb. 22, 1928, at the corner of Falls Road and Northern Parkway (known back then as Belvedere Avenue).
Today, traffic signals can be triggered by radar or electric fields responding to approaching vehicles. Adler's light reacted to a blasting of a car horn. (A sign posted by the police department encouraged drivers to STOP, SOUND HORN TO CLEAR SIGNAL.) These days, such a device would create Mad Max mayhem at the base of the mighty hill at Northern and Falls, with drivers wondering if oncoming cars were honking at them or trying to bully the light into staying green. But in the '20s, this was an easygoing country crossroads, which created its own set of problems: As the inventor explained to The Evening Sun in a 1977 interview, mooing cows often kept the sound-sensitive signals flashing.
From his inventive youth to his death in 1980 at the age of 81, Adler was devoted to making people and their machines move more safely and efficiently. Starting at the age of 14--when he installed a new and improved brake on his father's car (without letting dad know beforehand)--the Baltimore native went on to create or modify more than 60 devices, running the transportation gamut from cars to trains to planes. He perfected the classic flashing railroad-crossing signal, and versions of his aircraft flying lights are still used today.
Adler also designed a traffic signal intended to get motorists to slow down when taking a sharp curve. The "Adler Speed Control Signal," installed in 1936 on curvy Falls Road in Woodberry, would show red until the approaching car slowed to about 15 mph; only then would it go green. Speed demons who didn't ease up found themselves having to stop suddenly at the light. Alas, his solution for the age-old problem of tailgating--a meter on the dashboard that would show the number of car lengths between the driver and the vehicle in front--never took hold.
By all accounts, including newspaper articles and a paper his granddaughter wrote for the Jewish Museum of Maryland, Adler was the classic eccentric inventor--more interested in ideas than material things, possessed throughout his life of a childlike curiosity, most comfortable in old clothes pocked by holes burned by ashes from his pipe.
The son of a well-to-do physician, Adler fell in love at a young age with trains and never lost the fascination. He worked as a consultant for the Maryland and Pennsylvania Railroad for 20 years before devoting himself full-time to freelance inventing, and he located his office/workshop in the old Mount Royal Station so he could watch the locomotives. (He also amassed a huge model-train collection, natch.) His daughter--who wants to be identified only by her father's nickname for her, "Princess"--says he ran the household on "railroad time."
"Dinner began promptly at 6," she recalls, "and when you came running in the house late, he would look at his watch and say, 'It's 6:01.'"
One inventor stereotype he defied was that of the basement tinkerer. He didn't consider himself a scientist and didn't outfit his workshop with tools or laboratory gear, his daughter says--it was more of a study, he being more of an idea man. His designs, sketched on graph paper, were sent out to be built for him. "It wasn't like he was working on models or anything like that," Princess says. "He sat and thought, smoked his pipe, and watched his trains."
Though the trains were his passion, Adler adapted easily to the modes of transportation that would largely supplant the railroad during his lifetime. In the mid-'50s, he reportedly bought the first Lincoln Continental Mark II in Baltimore, and was so impressed with its engine that he replaced the standard hood with a transparent dome so he could watch the works run. (He went back to the original hood when the car's paint got repeatedly scratched by passers-by leaning on the car to steal a peek.) He also owned an airplane.
But for a man so engrossed in the mechanics of moving people, Adler himself lived a sedentary life. He preferred to stay home, reading and writing articles for publications ranging from The New York Times to the Baltimore Beacon, a now-defunct local monthly to which he contributed a regular column in which he discussed his work and interests from a variety of interesting angles--how he painted his Rolls-Royce fire-engine red, for example, or a meeting with Ernest Hemingway during which Papa paid tribute to Adler's work on aviation lights. In another Beacon piece, he bemoaned the replacement of his "Speed Control Signal" with police radar guns, a change he insisted was less about safety than money.
"The manufacturer of the speed control signal discounted its manufacture," Adler wrote. "In its place, he perfected a device to snare the motorist and to cost the motorist money in speeding violation fines to enrich the coffers of municipalities."
Adler's traffic-control devices may have been superseded by newer technology, but one monument to his transportation savvy remains--the Amtrak station at Baltimore/Washington International Airport, which Adler started urging the state to build back in 1964 (when the airport was still called Friendship). The station was completed in 1980; on the morning it was dedicated, Oct. 23, Adler died. In the next day's Evening Sun, it was the traffic pioneer's passing rather than the train stop's opening that made the front page.