OLD BUILDINGS seem to vanish overnight in Washington. Some turn into parking lots that eventually sprout steel-and-glass boxes. Others become vacant lots and then "Federal-style" townhouses. The city's tough new landmark law is expected to slow the slaughter, but many interesting old buildings still are doomed or in danger.

Go throw them a blow of the eye, as is said so much better in French, before the wreckers throw them blows of the steel ball.

Only a few of the dozen or so buildings that comprise HAMILTON ARMS VILLAGE are slated for demolition, but the storybook-looking complex, clustered around a grape arbor and a goldfish pool on 31st Street between M and N, is a goner. The tenants have been evicted from the 30 low-rent apartments that were lovingly decorated with fanciful sculptures, murals and carvings by late owner Molly Reid.

The new owner plans to gut some buildings, demolish others, and generally upgrade the place - and the rents. He is now dickering with the Commission of Fine Arts, which advises the District on demolitions and building permits in Georgetown.

In the 1700 BLOCK OF N, NW stand three brooding red-brick Romanesque Revival rowhouses designed by T.F. Schneider, the architect who also did the nearby Cairo Hotel. Owner John O. Antonelli, stepson of parking mogul Dominic Antonelli, says he will preserve the facades if he is permitted to build a 90-foot office building behind them.

Dupont Circle civic groups opposed the younger Antonelli's unsuccessful try for a zoning variance. When Antonelli sought a demolition permit as well, the citizens won that round by obtaining an injunction seagainst issuane of a permit, but the fight isn't finished. Take a walk down N Street, an oasis in the new downtown, and pause in front of Nos. 1752, 1754 and 1756.

RED LION ROW, the 2000 block of I Street NW, facing Pennsylvania Avenue across a small triangular park, would be better described as Shepherd Row. Several of the Italianate Victorian townhouse there were built by "Boss" Alexander Shepherd, the territorial governor of the District who moonlighted as a developer in the days, when conflicts of interest were ordinary perks of public office.

The block is listed on the National Register of Historic Places. It is also on George Washington University's master plan as the site of a revenue producing office building. And the Howard P. Foley Company wants to put a new headquarters building in place of several of the houses on the block that the university doesn't own.

Foley has tried to tear down two of the buildings - 2030, a Federal-style house built in 1830, and 2022, one of the 1870s Shepherd houses. Preservationists went to court to block both demolitions, but time, may be running out for these buildings. Preservationists hold out some hope that GW will acquire all the houses and turn them into a Lafayette Square-type arrangement with a high-rise behind.

But better hurry down to I Street if you want to see what architectural historians have called "the last commercial-residential block facing Pennsylvania Avenue between the White House and Georgetown to escape large 20th-century intrusions."

THE YWCA, a red-brick Georgian Revival-style structure at 17th and K Streets NW, is to be replaced by what is described as a "class A office building."

The building, dedicated by Grace Coolidge in 1928, has avid and vocal defenders but must, Y officials say, be sacrified to help get the organization out of financial hot water. The annex, formerly a residence for women, already has become a parking lot. You can buy chocolate-chip cookies at the 17th and K building until early 1981, when the Y will move downtown and that corner will go the way of the rest of K.

Another building that may be sacrificed as part of the Y's move to a lower-rent district is the JULIUS LANSBURGH FURNITURE STORE at 9th and F Street NW. In a complex deal, the Y bought Lansburgh's and turned it over to a Dominic Antonelli partnership, with the Y to to pay for demolishing the 1867 French Renaissance-style building and paving the rubble for a PMI parking lot.

In exchange for that plus some cash, the Y acquired a site at 9th and G. Before it became a furniture store in the 1920s the structure was a Masonic temple. The white Masons who commissioned architect Adolph Cluss to design it moved out in 1907. For more than a decade thereafter it was occupied by black Masons.

The new owners have offered to save it - if the city will let them gut the interior and build a 13-foot-high structure behind and above the 60-foot facade of Lansburgh's and if they get a grant to cover the cost of "rescuing' Lansburghs. This is the Planned Unit Development ploy, which created the extra-high towers that overshadow many human-scale New York City landmarks, Lansburgh's may be the local test case.

Owner of the MAYFLOWER HOTEL say they are considering a facelift that will make the familiar 1924 Connecticut Avenue landmark unrecognizable. Architect Vlastimil Koubek is working on plans that call for the razing of the avenue facade.Some of the hotel would be converted to offices and the interior would become a Hyatt-hotel-type atrium with one of those scary elevators. A decision on whether to proceed probably will be made within the year.

While waiting in vain to move into the White House, James G. Blaine, the Harold Stassen of his day, built a dour red-brick castle at 2000 MASSACHUSETTS AVENUE NW. Converted into offices, the somewhat shabby mansion stands as a reminder of Dupent Circle's fashionable heyday. How long it will stand is in question. At a recent hearing on a proposal to rezone the area to make it less attractive for developers to tear down old buildings and put up highrises, the owner said he would like to redevelop the site, preferably without the house.

Washington's senior surviving commercial building, the RHODES TAVERN at 15th and F, is in the way of a multimillion-dollar shopping mall and office building. Built in 1800 and used as the British command post during the sack of Washington in 1814, the much-altered building now houses a fruit stand, a souvenir shop and a newsstand.

Two groups have been negotiating for a year with developer Oliver T. Carr to save the Rhodes. Carr has offered to donate the tavern plus $100,000 to a "responsible group" that would move it. So far, no takers.

Two other buildings threatened by the same development are the ALBEE-KEITH'S THEATER and the METROPOLITAN BANK, facing 15th Street between F and G.

Both of these imposing Beaux Arts-style buildings with copper mansard roofs were built about 1912 and are considered architecturally more significant, though less historic, than the neighboring Rhodes Tavern because they forge a visual link with the Treasury and with the financial district farther up 15th Street.

The Metropolitan Bank Building is slated to be saved, if the city passes special legislation changing the height limits on the block, and if it closes an alley behind the building. But the Albee Building is already being hacked away. By press time half the building - the vaudeville-theater-turned-movie-palace - probably will be gone. Carr is asking for a $5.1 million subsidy to save the facade and part of the side of the building. City planning official James O. Gibson this week announced a $1.25 million proposal he thinks Carr and everyone else involved will find acceptable, the money to come from a mixture of federal funds and tax abatements. Carr has said saving the facade would cost $3.5 million. The news is heartening, but watch that space.

The OCCIDENTAL RESTAURANT and the adjacent OCCIDENTAL HOTEL in the 1400 block of Pennsylvania Avenue were built by Henry Willard, whose brother Joe built the hotel next door that bears the family name. The small but elegant Beaux Arts hostelry opened in 1903; the restaurant opened in 1914 and was the Sans Souci of its day. Under a plan for the block recently approved by the Pennsylvania Avenue Development Corporation, both Occidental buildings would disappear as part of the plan to revive the Willard. Since the Willard brothers never got along, Joe is probably turning gleeful somersaults in his grave.

Urban renewal has long had its icy grip on downtown, especially in a two-block area between 11th and 13th and G and H Streets NW now known as the METRO CENTER PARCEL. The urban renewal plan for the land calls for destruction of all the buildings that aren't at least 110 feet high, which covers just about all of them. Officials of the Carr Co., which is negotiating to develop the site, say they will consider retaining some of the buildings if the community will support a change in the urban renewal plan. Some of the otherwise doomed buildings that may be considered for salvation during upcoming public hearings include:

Sloan's Auction House, the city's oldest, a five-story Victorian structure with a profusion of cupolas at 715 13th Street NW.

The Washington Project for the Arts (WPA) Building at 1231 G Street NW, an 1892 group of stores with a large second-floor hall that once housed a university.

The Carolina Apartments, 702-710 11th Street NW, built in the 1870s with a seven-story addition in 1901 that created a total of 30 flats and three stores. It's an early Victorian structure that shoppers on 11th Street rarely look up to see.

A 1910 firehouse at 719 12th NW with a tile roof and a brick-stucco frieze.

Churches sometimes find that old buildings stand in the way of God's desire for a grander house of worship, a Sunday school or a parking lot. Several years ago a Baptist church incurred the ire of the Capitol Hill Restoration Society by tearing down a high Victorian structure that housed a cafe named Mary's Blue Room.

Now another Baptist church wants to tear down two stately Romanesque Revival-style houses at 600 AND 602 MARYLAND AVENUE, NE. Demolition of the circa-1880 houses has been halted while the church's architect negotiates with a more preservation-minded one. But if push comes to shove. . . .

In the 1850s Thomas Ustick Walter, who designed the Capitol dome, planned an Italian-style villa for the Ingle family. INGLESIDE still stands, as part of the Stoddard Baptist Home for the elderly at 1818 Newton NW.

Trustees of the home want to raze it and build a new one. Preservation-minded Mount Pleasant residents want them to remodel Ingleside. Over the protests of the trustees, the villa was recently declared a landmark. The trustees are looking at design alternatives but indicate that they might try to secure a demolition permit, probably pleading the social merit of the proposed new home for the elderly.

On the northwest edge of WASHINGTON CIRCLE stand, for the time being, six turn-of-the-century rowhouses. A developer wants to replace them with a 105-unit high-rise condominium. The Foggy Bottom Advisory Neighborhood Commission has applied for landmark status all buildings on the cirlce.

Since under law no demolition permits are issued while a landmark application is pending, the developer is furious. Claiming that he had invested considerable funds, he is threatening to sue the ANC commissioners personally. No date has been set for the landmark hearing, but it is expected to be lively. Go take a look at 2305, 2307, 2309, 2313, and 2315 Washington Circle.

Henry Wardman, an English boy who wanted to emigrate to Australia but took the wrong boat and made it big in real estate here instead, built a crescent-shaped hotel named the Wardman Park in 1918. Now known as the SHERATON PARK, the hotel at Connecticut Avenue and Woodley Road is to be demolished this month.

"People who go to conventions don't want to stay in an old hotel," a spokesman said.

One happy note: the Wardman Tower, the apartment building on the hotel grounds that housed celebrities from Perle Mesta to Spiro T. Agnew, will remain.

The WYOMING apartment house at 2022 Columbia Road NW was built around 1900 by prolific local architect T.F. Schneider, mastermind of the Cairo Hotel. Now the Washington Hilton around the corner reportedly in angling to buy the Wyoming plus two adjacent apartment houses and replace them with convention facilities. The building's owner, who lives in the Wyoming, does not deny that Hilton is interested, but says he doesn't have "the slightest idea? whether he'll sell. Before he makes up his mind, peek into the spectacular Hollywoodish lobby.

One of the city's few Gothic mansions stands vacant and forlorn at 1333 16th STREET NW. Built in the 1980s and remodeled in 1914 by George Oakley Totten, the architect who helped make 16th Street the "avenue of presidents," the house is now owned by the government of Nigeria.

The Nigerians want to tear the house down and build a modern chancery. They applied for a demolition permit a few months ago, but a hearing before the landmark committee was cancelled at the last minutes. The block was recently downzoned, meaning that the chancery can't be as big as the Nigerians want. The State Department tried to intervene in the zoning process on behalf of the Nigerians, but to no avail. While the Nigerians explore their options, hurry on down to 16th Street. CAPTION: Pictures 1 and 2, no caption