Every so often, cyclists approaching Hains Point do a double take at the 81-year-old Inlet Bridge. The fish-tailed gargoyles on the walls there seem misplaced: gleefully spewing water, their mildly sinister faces recall cartoonist Mark Alan Stamaty's Congressman Bob Forehead. Or a twisted Darren from "Bewitched".

With their ski-jump noses and side-parted hair, the imps indeed depict a modern-day bureaucrat, admits sculptor Constantine Sephralis, who created them in 1987. At the time, when the National Park Service was repairing the bridge, its fish-shaped gargoyles were removed for safekeeping -- and promptly stolen.

"We thought it would be a good idea, since the chief of the park was retiring, to play a little joke," says Sephralis, a veteran sculptor from the Washington Cathedral who was hired to replace the two gargoyles. "He retired about two years ago, Mr. Jack Fish. He was the chief of the national park system, so we thought, maybe we make a little Fish fish." Park Service officials supplied a photograph to serve as a model; the gargoyles were a surprise for Fish, who likes them, Sephralis says.

All over Washington, such secrets wink out at you: from a cherished monument, from a ritzy apartment complex, from the very bricks in the White House. Grand public works, it seems, are irresistible sites for private jokes -- and subversiveness.

In some cases, supervisors of public works may welcome an artist who can add a special touch. The historical figures that adorn buildings all over Washington -- the Supreme Court, for example -- sometimes include a likeness of the architect as well. On the Supreme Court pediment, the triangular tablet over the entrance, portraits of the building's architect and sculptor mingle with allegorical figures. "Maybe it's tongue-in-cheek" on the part of the planners, speculates George Gurney, associate curator of the National Museum of American Art, "or maybe it's the realization nobody knows what these people looked like anyway."

Along the same lines, some modern-day Freemasons suggest George Washington may have given the nod to the Masonic symbols carved on dozens of White House foundation stones. John Platt, curator of the Masonic Library and Museum of Pennsylvania, says the stones surfaced during renovations under President Harry Truman who, like Washington, was a Freemason.

There is some debate whether the symbols were carved by purely "operative" masons -- who actually work with mortar and stone -- or masons from the philosophical fraternity, concedes Stephen Patrick, curator of the George Washington National Masonic Library in Alexandria. "There may have been something to do with leaving a mark for their supervisor ... or sort of the same thing if you go into a building that's been erected today and the workman wrote 'Johnny loves Susie' on the boards," Patrick says.

Truman, however, was tickled by the discoveries. Since there were just enough for each Masonic jurisdiction nationwide, the president presented each group with a stone as they were dug from the White House basement, Patrick says.

When it comes to more visible stonework, a nod from authorities can be crucial for personal imprints to survive. Stone carving is an expensive proposition, especially when costly scaffoldings are involved. That's why cathedrals, with their lofty, nearly invisible surfaces and a tradition of whimsical decoration, are special havens for political and fantastical detail. At the Washington Cathedral, for instance, Sephralis gained carte blanche to create his gargoyle "hippie" (located on the building's south side) during the Vietnam years.

But even gargoyle-makers meet institutional hurdles. One architecture critic tells of a master stonecutter at the cathedral who took one liberty too many by sculpting a downright risque' rosette. Just as the tiny, highly situated ornament was completed, the critic says, a cathedral official happened by and ordered the racy rosette cleaned up. The censored version still exists somewhere on the building, a cathedral worker says. But cathedral representative Jean Grigsby, who hoped the tale would be squelched altogether, declined permission for the master carver to discuss it.

Negotiations between patrons and artists are routine in the creation of public works. But in recent cases in Baltimore and Richmond, artists followed strictly personal inclinations when they planted seeds for scandal in their publicly commissioned works.

Graphic artist Don Schnably paid dearly for his prank in a detailed cartoon of townspeople at play, meant to announce the 1987 Baltimore City Fair. When the ad appeared in a local newspaper, readers were abuzz -- about the couple depicted having sex on the merry-go-round. Amusing to some, the joke was termed a catastrophe by Baltimore's transportation department, which contracted the ad. One official in charge was "physically sick" with embarrassment, a witness said. Schnably, who was a partner in his own advertising agency, ultimately resigned.

The District and its environs aren't the only places where such high-brow high jinks take place. Perhaps the best-known was perpetrated at New York's Rockefeller Center by Mexican muralist Diego Rivera in 1933. Contracted by Henry Ford as an ode to capitalism, Rivera's vast "Men at the Crossroads," teemed with vignettes of American life. But one scene of workers celebrating May Day particularly reflected the communist Rivera's own vision: As the mural progressed, it became clear that the figure leading Rivera's sturdy American working men was the spitting image of Lenin.

Ford caught the allusion and vetoed it; Rivera rebelled. Finally, amid protests from Depression-era intelligentsia, Ford paid Rivera his commission but halted the painting, and eventually ordered the mural chipped off the wall.

In a 1987 case that made national headlines, Tennessee sculptor Maria Kirby-Smith created an $80,000 statue -- commissioned to honor slain Richmond law enforcers -- with a picture of a pig and the slogan "oink proof" on the bronze police officer's sole. In printed accounts, Kirby-Smith called the etchings a joke, which could be sanded off "in 10 minutes." Outraged citizens and police officials soon had the images removed.

Kirby-Smith struck again six months later, this time on an 800-pound bronze likeness of Sen. Strom Thurmond (R-S.C.). On the $24,000 statue, commissioned for the Edgefield, S. C., courthouse, a crawling cockroach was discreetly etched in the metal. The statue had been standing since 1984. Once again, Kirby-Smith shrugged off the scandal -- the insect, she reportedly said, symbolized "what was bugging the project and what was bugging me, the lack of funding and the changes."

Although she maintained she'd wanted the foundry casting the bronze to erase the offending roach, Kirby-Smith also reportedly said that "many artists add a personal touch to their works as commentary, for whimsy or to catch attention." The artist now cannot be reached to comment. But Thurmond, for the record, said he was unfazed by the affair.

Community organizer and former Yippie Dennis Livingston says he nurtures a special interest in this tradition of disruptive art and artists. "Goya, Caravaggio and Rembrandt are shining examples," asserts Livingston, now a graphic artist in Baltimore. "These are people who were hired by the courts to paint the aristocracy and flatter them," but rebelled by painting sexually suggestive images or grotesque portraits.

"Their existence was totally contingent on being subsidized by the very people whom frequently they despised. Eventually their art became so subversive they were chased out of the courts," Livingston says.

Other artists, through greater subtlety or smaller provocation, manage to preserve their private statements along with the commissioned work. Subversive touches lose some of their edge, for example, when they take the form of architectural quips. Hence the rapscallion "guardians" carved on stately 2101 Connecticut Avenue NW, a 1928 apartment building. In his recent book, "The Best Addresses," historian James Goode points out that the 16 grinning demons each brandish stone boulders, threatening to loose them on visitors.

Further uptown, the sculptor of Alban Towers on Wisconsin Avenue NW digressed from its neo-Gothic decor just enough to honor a 20th-century marvel. From the building's limestone entranceway or porte-cochere, six stone figures look out: five are garbed in medieval attire but the sixth sports an aviator cap, goggles and a bit of rippling scarf. The carving doubtless commemorates Charles Lindbergh's 1927 flight to Paris shortly before the building was finished, Goode says. But he adds he's uncertain if the aviator was the brainchild of the architect or the sculptor.

Somewhere between nose-thumbing and a mere gentle tweak falls the work of New Deal muralist Rockwell Kent, also influenced by the new age of aviation. According to curator Gurney, Kent was hired in the 1930s to paint murals celebrating the first airmail delivery to Puerto Rico. Created for the 12th Street building that stands between Constitution and Pennsylvania Avenues (next to the Federal Triangle Metro stop), Kent's work "made a big stink because he made an allusion in language that nobody understood," Gurney says.

Specifically, the lines were in an Eskimo dialect. In a somewhat oblique protest of Puerto Rico's territorial status, Kent had inscribed: "To the people of Puerto Rico our friends ... let us change chiefs. That anyone can make us equal and free." Once translated, the statement was roughly criticized. And forgotten. "Kent was asked to substitute the words, but actually the inscription was never changed," Gurney says.

And yes, long before Jesse Helms, artists and patrons squared off over claims of obscenity. Union Station's Roman legionnaire statues, sculpted by Louis Saint-Gaudens in 1906, are an early casualty of this battle. The French sculptor had agreed to complete the figures upon approval of plaster models, but railroad officials balked when they saw Saint-Gaudens's work.

Voicing "deep concern" that the statues' bare legs would perturb women passengers, the authorities demanded that Saint-Gaudens clothe his soldiers more modestly. Arguing that any change would mar the work's symbolism, Saint-Gaudens stood his ground. Finally, the two sides agreed that large shields could keep the soldiers both authentic and seemly. The gesture may just have prompted more whispers. Saint-Gaudens made a third of the statues -- the ones with both hands on their shields -- stark naked underneath, and if you peer carefully from the side at the one on the rotunda's far left as you walk toward the Metro, "well, there's one up there that everybody always laughs at," says Amtrak employee Jackie Beigie. "He's definitely anatomically correct."

Sometimes the viewer's imagination, and not the artwork, is where scandal lies. Visitors to the Lincoln Memorial look for their own hidden messages, says historian Michael Richman. Editor of an upcoming book about the creator of the Lincoln Memorial, Richman debunks one of public art's more tenuous myths: that sculptor Daniel Chester French carved Lincoln's hands to form the sign language letters "A" and "L".

"It is totally coincidental, and Gallaudet College (for the hearing impaired) is responsible. It's a sort of good-natured conspiracy after the fact," says Richman, who once lectured on the topic to an enthusiastic Gallaudet audience. "The connection was that French made the statue of Thomas Hopkins Gallaudet that's on the campus. A young student is depicted there with Gallaudet and she is forming the letter 'A'."

But, says Gallaudet graduate Sherry Bravin Duhon, students believe the legend -- regardless of what French actually carved.

"We don't know if it's intentional but in the deaf community we want to believe it was intentional," says Duhon, who now works in the Gallaudet visitors' center and tells the legend to newcomers.

"Every time deaf people go to the Lincoln Memorial they always make sure to look at the hands," she says. "Lincoln was a very powerful man who chartered the university, so it's a symbol to me of openness to deaf people. When I look at the Lincoln Memorial, I thank him."