When he was at a Wizards game at MCI Center a couple of years ago, Eddie Hill caught himself tallying heads. Just for the hell of it, he was breaking up the arena visually and adding up the game attendance, section by section.

“I’ve gotten to a point now where I’m in a crowd of people, and I find myself counting,” explains Hill, seated in a booth at a downtown Burger King on a recent Tuesday. When the game attendance later was announced over the arena speakers, he says, “It was like, Huh—I was pretty close.”

After working for 22 years with the Washington Metropolitan Area Transit Authority as a traffic clerk, Hill has resigned himself to the fact that his mental clicker is going to work overtime. The 57-year-old spends most of his days riding city buses for research purposes, counting precisely how many passengers get on or off at every stop on a particular line. The transit authority uses the data he collects to adjust its routes and timetables. The agency employs about two dozen people to perform this monotonous task, but no other employee has come close to equalling Hill’s longevity. His boss, Ronald Saunders, says the second-longest traffic-clerk tenure is about seven years.

“Nobody comes here with the aspirations of retiring as a traffic clerk,” says Saunders, who tells his new clerks that he prefers they move on after two years of counting. “Eddie’s a little different. This is a job that kind of fits him.”

The distraction of incessant tallying notwithstanding, Hill’s job as a passenger counter allows him to indulge three obsessions: local geography, public transportation, and motion itself. Washington’s bus system is notorious for its unreliable schedules and lack of available maps, but Hill, who lives in Adams Morgan and rides most of the roughly 150 lines at least once every year and a half, has committed to memory not only the lines’ routes and timetables but also their rhythms and dispositions.

For instance, take the L2, which, running through Chevy Chase, Md., is a favorite among the geriatric crowd. “Seniors receive their checks on the third of the month,” says the mustachioed Hill, talking with a residual Charlottesville, Va., drawl. “So on the third and for the next four or five days, you can tell a difference in the rides. Little old ladies who are able to carry two shopping bags might try to carry four. That takes time. The operator will have to help them get on and get off.”

There are the ethnically diverse routes, such as the 42 (“50 people, 20 languages,” he says); the socioeconomically stark, such as the D2 (“menial workers and big-time lawyers”); and the leisurely and scenic, such as the P17 (“You can see Virginia, D.C., and Maryland, all on the same trip”).

As he boards the empty P17 at 17th and H Streets NW shortly after 3 p.m. for a ride count, Hill lays out the route’s stops in detail and offers a demographic glimpse of the line: “These are working people, middle-class. They have quite a long ride in the morning, so they’re tired by now.” Upon request, he also predicts ridership numbers for the run: “It’ll average probably about 22; on the high end, 35.”

He takes the fourth seat on the side opposite the driver. “This is a great spot. You can see all the movement between the front door and the rear door,” he says. At each stop, Hill will mark down how many passengers climb aboard, how many exit, and how many the bus is left with. He accomplishes this by keeping his head on a swivel, but, when things get hairy, he’s learned to stare straight ahead and observe both doors with his peripheral vision. After two decades, he says, he can feel passengers boarding and alighting merely by the shift in weight on the bus.

Six passengers climb aboard, Hill marks it down, and the bus is off. More riders take a seat at each stop, and as the bus approaches Pennsylvania Avenue and 10th Street NW, Hill says, “I know this line. Nobody gets off here.”

Nobody gets off here. Four more climb on.

The bus cuts its way through the National Mall and heads south on South Capitol Street. As it crests the Frederick Douglass Memorial Bridge over the Anacostia River, Hill turns in his seat and points to the steeple of the Masonic Memorial in Alexandria. “Doing ride checks, you notice things that the average person doesn’t notice,” he says. “You’re seeing buildings, pedestrians, changes around the District.”

Bus travel and sightseeing inspire Hill’s nighttime work as a country music singer. He’s played sporadically in bars in Adams Morgan and Dupont Circle, and his original songs include an ode to the famous black cowboy Bill Picket (“We like your style, Bill Picket/’Cause you’re wild and you’re wicked/When you grab that bull by the horns”), as well as one to Washington’s transit authority (“We’re public transportation that you can trust/So park, sit, and ride, and leave the driving to us”).

By the time the bus reaches the District–Maryland line, Hill’s crowd assessment has proved spot-on: The bus is dead silent, and about half of its 34 passengers have nodded off in their seats. “Working people,” he reiterates in a whisper. Just over the Prince George’s County line, two more passengers board the bus.

As Hill has divined, the very first passengers to exit the bus do so at the Oxon Hill Park & Ride. “Now we’ll only be discharging,” he says. Enumerating the groups that scamper down the two sets of stairs requires surprising dexterity, and at each stop Hill performs a subconscious ritual much like a batter stepping into the box at home plate: He runs his hand over his clipboard in a clockwise circle, turns his head to the left, turns right, turns left again, checks his watch, then marks down the count.

The bus presses on between the tidy town houses of Oxon Hill, a few passengers hopping off at each stop, until the final 10 riders exit together at the Fort Washington Park & Ride. Now the bus will retrace its route back into downtown D.C., riding “deadhead,” or empty and out of service.

Hill checks his clipboard to make sure his numbers are in order. Running his hand down a column, he notes that ridership topped out at 36 passengers. His pre-ride prediction was off by just one.

“Pretty close,” he says.CP