May Festival 1995, which took place Sunday afternoon in the 3700 block of Brandywine Street NW, could be called an outdoor concert of folk music. But it also resembled a block party, a Renaissance fair and a Druid fertility rite. It is a spinoff from the Washington Revels, which take place in the Lisner Auditorium each year before Christmas, and the undertone of its festivities is the changing of the seasons, the constant struggle of one natural force against another and the temporary triumph of summer over winter, life over death.

"These are good spirits that we bring/To observe the ancient rites of spring," intoned Mary Swope, organizer of the festival, in the opening invocation. In fact, short shrift was given to the few evil spirits that made brief, symbolic appearances during the festivities. Most of the events were sun-drenched, like the perfect weather that shone on the celebration.

A May Queen was crowned and took her throne on the front porch of one of the houses, next door to the house whose porch had been transformed temporarily into the Bull and Bush Pub, serving beer and wine, spritzers and hard cider.

There was a maypole in the middle of the street. Its streamers were taped to the pavement until, near the end of the long afternoon, the maypole dancers picked them up and danced around in intricate patterns that left the streamers wrapped around the pole.

A black and red "Obby Oss" (that's British for "Hobby Horse") danced through the crowd surrounded by euphoric acolytes, spreading (we were told) luck and fertility to Brandywine Street.

A variety of Morris dancers (male and female in separate groups) pranced down the street with clusters of bells strapped to their shins, engaging in mock battles with clubs and waving kerchiefs. A wild variety of costumes could be seen in the audience as well as among the entertainers, and many who did not have medieval or Renaissance garb wore wreaths, ribbons or T-shirts that made statements.

Much of the time, the audience merely stood, watching and applauding. But for some songs, the spectators were vigorously induced to participate, with the help of a good chorus on stage and carefully prepared volunteers who had been planted here and there to give encouragement and example. The most spectacular audience participation feat undoubtedly came when the bystanders suddenly found themselves divided into a four-part chorus lustily singing the ancient and seasonally appropriate round, "Sumer is icumen in." Afterward, the audience applauded itself enthusiastically and justifiably.

During a "Sheepshearing Song" the singing was left to the chorus, but audience participation included children petting a sheep brought in for the occasion. A minute later, the street had been cleared and children from Sidwell Friends school were dancing in circles and singing "Oats and Beans and Barley Grow" and "There's a Place Called Mars."

The underlying theme of struggle included brief portrayals of St. George slaying a dragon, Robin Hood fighting Little John and St. Michael defeating Satan.

But the most elaborate and dramatic theatrical event was "The Battle of the Elements," in which Earth, Air, Fire and Water engaged in a four-way argument, verging on violence and slipping deeply into slapstick humor when Water (clad in a green bathing suit and bearing an oar and a pitcher) threw water balloons at Fire (sporting a firefighter's helmet), who flung back a terrible curse: "Evaporate."

They were finally brought to order by a seed, who reminded them that she depended on all four elements (earth, sun, air and water) to become a tree, and they reached harmony on this theme: "Now we know, for life to grow, we all must work together."

It is hard to imagine that the demons, druids, dancers and other wild creatures of that wild afternoon are now back in government bureaus, law offices and university classrooms pretending to be ordinary Americans, but surely life in Washington is richer today because of the rites in which they engaged on Sunday.