Harold Lloyd in Speedy, one of the entries in the series The Silent City (Photos: Film Forum)

How easy to forget that silent movies -- even the comedies, with their flapper-and-dandy get-ups, their cheery ragtime scores -- could be sharper and more politically aware than many of the sound films that followed. Perhaps the former vaudevillians of the new Hollywood felt free to be blunt before the camera. Perhaps California's sunshine separated producers, for one brief decade, from their conservative senses. Whatever the case, Film Forum's new series The Silent City (opening tonight and continuing weekly through Aug. 27) confirms that silents, as daffy or corny as they can get, didn't flinch from realities of class and sex. Not yet weighed down by the sound equipment that later would anchor film crews to indoor sets, silent filmmakers were also freer to shoot on location. The result -- especially in films that take place in real, iconic places like New York, as these do -- are movies that feel palpable and gritty though their tone remains optimistic.

The comedies show the difficulties and absurdities and humiliations of trying to make a living in New York while a patrician upper set frowns down and, ultimately, either steps aside or is won over by a working-class hero. In It, Clara Bow is Betty Lou Spence, a spunky salesgirl in a department store who falls for Cyrus Waltham Jr., the owner's son. Her chances are slim, especially after her roommate's fatherless child is mistaken for her own. But no social stigma can keep Betty down, and she wins Cyrus Jr. in the end without betraying her morals or her roommate. (In relative cultural terms, the subplot about the illegitimate baby is a far more candid depiction of sex and its consequences than you find today in, say, Knocked Up.) Speedy stars Harold Lloyd as a feckless young man who can't keep a job although winning his sweetheart, Jane, depends on it. Her grandfather runs the city's last horse-drawn trolley. In a storyline that anticipates the little-people triumphs of Frank Capra, Pop's trolley is almost squeezed out of service by a powerful businessman until Harold persuades the local tradesmen to help him clobber the businessman's hired goons. In The Cameraman, Buster Keaton plays a tintype photographer (already a dinosaur in 1928) who wins the girl, Sally, by hustling for a job where she works, at the MGM newsreel agency.

These pictures set their most important events in public places and lavish on the audience all the chaos that implies. Keaton falls for his girl, almost literally, on a Manhattan street, in the midst of kind of a flash-mob. It's the pressure of the crowd that pushes him up against her (although Keaton was known as "The Stone Face," his phizzog, to use the old vernacular, displays in under three seconds all you need to know about how a woman's fragrance can affect a man). The climaxes of both The Cameraman and Speedy turn on different forms of mob violence. To watch silent comedies set in New York is to be injected into the crowd and feel yourself ground up by it, just as the main characters do.

These films sympathized so boldly with the masses because the masses were the ones watching. But audiences were made up largely of the working and middle classes during the Depression as well, when musicals and screwball comedies were often awash with satin and set in hangar-like ballrooms. (There were exceptions, of course, like Hands Across the Table, a delicious romantic comedy with Carole Lombard as a hard-up manicurist.) When I recently spoke to Bruce Goldstein, Film Forum's repertory programmer, he suggested a simpler explanation for all this plebeian solidarity, saying that in the silent era working-class life was more picturesque. "The places the rich went to weren't as photogenic as Coney Island was in the '20s," he said.

Indeed, four of the films in this series make pit stops in Coney Island (though not all were filmed on location). But perhaps the city is most evocatively portrayed in the silent comedies because jokes before sound called for literal collisions between characters and their environments. In silent melodramas like Regeneration, also at Film Forum this month, the city is an abstract skyline behind the hero and heroine: she, a rich young social worker, struggles to help him, an orphan who grew up into a gangster, reform himself. The story is conveyed with alternations of longing glances and intertitles. But in The Cameraman, when Sally helps Buster make his way as a rookie cameraman, the obstacles he faces are physical, not metaphysical. His first attempt at filming something newsworthy begins with him acrobatically hitching a ride on a speeding fire engine only to be driven straight back to the firehouse -- a pantomime of pointlessness.

Buster Keaton joins rush hour in The Cameraman

The visual puns so central to silent comedies produced a world that looked unavoidably solid even on the silver screen. Objects like unobliging fire trucks might be deployed with comic-strip exaggeration, but the objects themselves remained concrete and realistic. (For a pure glimpse of that vanished world, it will be worth catching the Aug. 27 program New York Treasures from the Library of Congress, which brings together documentary clips of the city originally preserved as paper prints.) In the comedies the city becomes a character with a difficult, distracting personality of its own. And many of the city-centric jokes still exact a pang of recognition. It would be helpful, most mornings on the subway, to have a boyfriend who could string a dollar bill using bubble gum, tempt a seated man to pick it up and, in a blink, install his girl in the barely-vacated seat. But, ladies, we can't all be dating Harold Lloyd.

Maybe the silents’ fascination with the petty stuff of pratfalls -- the bubble gum, the banana peel, the ingeniously rigged-up gizmo -- accounts for the films’ expressiveness on the subject of class. In The Cameraman, Buster Keaton gets in a fix as he's preparing for a date with his girl: In his boarding-house room (whose modest décor is itself a sad joke), he ends up brawling with his piggy bank, collapsing his bed, hammering a hole in the wall and braining himself just to get at the coins. It's a classic (and not altogether fresh) bit of silent business, but the nub of the situation is that he's so poor he can hardly afford an afternoon out. The Cameraman was released in 1928; within a year, cash flow problems would be no laughing matter. Maybe timing is behind the frankness and freedom of the (American) silents: Mostly made between victory in the first World War and the onset of the Great Depression, these films could afford to laugh at even the delicate stuff. Whatever the explanation, the rare times you can see them properly -- on a big screen, with live piano accompaniment (incomparably better than recorded soundtracks) -- are not to be missed.