Orson Welles famously quipped that making movies was “the greatest electric train set any boy ever had,” and that spirit of fun has possessed filmmakers for more than 100 years now.

In typical kids-at-play fashion, each new generation of filmmakers and film lovers apparently needs to rediscover truths that the previous generation thought they had arrived at independently. Minicam toting children of Sundance take for granted that today’s new technology has liberated them from the economic and practical encumbrances of lights and sets.

If they’re willing to look back through film history, they’ll point to John Cassavetes as the godfather of quick, cheap, and dirty location shoots, or shout out to the Italian neorealists who made films amid the rubble of postwar Italy. But a new series at Film Forum called “The Silent City: New York in the Movies, 1898–1928,” which will play for the next five Monday nights as a sidebar to the ongoing “NYC Noir” retrospective, provides a vivid reminder that people were cranking cameras on our fair city’s sidewalks before the ink was even dry on Edison’s patents.

Among the many pleasures contained within Ted Wilde’s hilarious and high-octane Harold Lloyd, uh, vehicle “Speedy” (1928) is a reminder that Washington Square Park wasn’t always the NYU film student’s designated Monument Valley. During the big chase in Lloyd’s fast and furious farewell to silent movies, Speedy Swift drives a horse-drawn carriage into the park and right under the famous arch. Typical of Lloyd’s ruthlessly energetic and entertaining peak films, “Speedy” offers something for everyone. Yankees fans can thrill to an on-screen cameo from an obscure ex-Red Sox named Babe Ruth. The distant funhouse mirror of “Speedy” also offers a lengthy and detailed view of Coney Island’s old Luna Park, rendered poignant and timely by this fall’s imminent padlocking of Astroland and the wholesale development of the Coney Island waterfront that is supposed to begin shortly thereafter.

“Directors with vision like F.W. Murnau, E. A. Dupont, Fritz Lang, and Ernst Lubitsch had freed the camera from its immobility,” the Texas-born director King Vidor once said about the brainstorming behind his remarkable New York drama “The Crowd,” which was set in 1928. Vidor’s decidedly non-slapstick story of a broke couple’s ebbing fortunes in the big, lonely city features an intentionally downbeat vision of Coney Island — in contrast to Lloyd’s playful tableau in “Speedy.” “The Crowd” literally covers more NYC ground than almost any other silent film. In order to capture the city unawares, Vidor and his crew hid a camera and an operator inside a mocked-up pallet of boxes on a pushcart and took sidewalk-level footage of New York playing itself, from the Bowery to Times Square.

When offered the directorial reins of the 1915 proto gangster picture “Regeneration,” Yonkers-born cowboy Raoul Walsh logically and thriftily chose to shoot the film’s skid row scenes on the Bowery itself. “There were enough bums and winos around to cut down on extras,” Walsh wrote in his memoir. But when it came time to cast extras for the film’s climactic boat fire, Walsh made some questionable hires.

Viewing the finished film, producer William Fox noticed that the women extras jumping ship into the Hudson River were noticeably short on undergarments. It turned out that Walsh’s streetwise casting assistants had responded to the director’s request for more female background players by recruiting from the ranks of the city’s immodestly under-clothed streetwalkers. “The censors will hang us!” Fox said. But an 11th hour application of hand-drawn undies saved Fox and Walsh from the Legion of Decency, even if “some of the women looked like they were wearing diapers,” as Walsh later admitted.

“Regeneration” appropriately screens with Walsh mentor D. W. Griffith’s 1912 “The Musketeers of Pig Alley,” which is probably the first dramatic film set in Manhattan’s underworld or “New York City’s other side,” as a title card describes the film’s Lower East Side locations. “This picture production, which does not run very strong as to plot, is simply intended to show vividly the doings of the gangster type of people,” the Biograph Company’s promotional literature modestly claimed. True enough, Griffith and his co-scenarist Anita Loos’s script isn’t exactly a nail-biter. But thanks to Griffith’s eye and his pioneering cameraman Billy Bitzer, the soft-hearted melodrama in “Musketeer” provides a sharply focused view of a back-alley urban Atlantis that, though vanished beneath nearly a century of increasingly upscale real estate, still silently calls from the silver screen.

Through August 17 (209 W. Houston St., between Sixth Avenue and Varick Street, 212-727-8110). A number of screenings, including “NYC Treasures From the Library of Congress,” will feature live piano accompaniment by Steve Sterner.