The parks of Washington are one of the city's glories -- not only the great parks of Rock Creek, the Potomac and the Mall, but the small circles and squares. Designed by L'Enfant in his plan for the new capital, they have been cherished, embellished and enjoyed ever since. But now Lafayette Square, handsomest of the downtown parks, is no longer a place to delight the eye and invite the passer-by.

Now Lafayette Square has become the rallying point for demonstrators, protestors, placards, signs, banners, loudspeakers and tents.

And it can no longer provide an adequate forum for the First Amendment needs of the demonstrators. In the last few years the numbers have multipled so that crowds spill over onto Pennsylvania Avenue and are a great worry to those concerned with the safety of the president.

The right to free speech, the right to dissent, are guaranteed by our Constitution. And certainly the great men whose statues adorn the park's four corners: Lafayette, Rochambeau, Von Steuben and Kosciuszko, who came from France, Germany and Poland to help in our revolution, believed in challenges to the established order. Then there is the heroic statue of Andrew Jackson on his horse in the center of the square. He listened to the voice of the people. None of them would want to deny today's citizens a place of protest.

But does it have to be Lafayette Square? Behind the White House is the Ellipse, a large open space only filled during the Christmas season's Pageant of Peace. Couldn't the Ellipse be used as Washington's place of protest, Washington's Hyde Park? There would be more room for demonstrators, for speakers and for paraphernalia of dissent.

Think what a joy it would be to have Lafayette Square again a thing of beauty, where people can walk, admiring the White House, the long vista up 16th Street, St. John's Church and the facades of the houses preserved by the intervention of President Kennedy.

The park could then be restored to its traditional use as a "public pleasuring ground" and as the site for great national events. There the inaugural stands go up every four years. There somber crowds have mourned the deaths of presidents. And there jubilant crowds have celebrated victories at the ends of wars.

This year, soon after the Pageant of Peace on the Ellipse is over, the building of the inaugural stands in Lafayette Park will get under way. It seems the right time to establish the city's new Hyde Park on the Ellipse. This could be accomplished by executive action through the National Park Service or by congressional action.

Lafayette Square could then be returned to its beauty and serenity.