On a recent sunny Sunday, Janine Smith of Gaithersburg and more than 20 other people crowded into a Washington apartment in response to a call from the Folklore Society of Greater Washington to "Get Into Shapes."

No, these were not health enthusiasts. The members of this group, some of whom were meeting each other for the first time, were gathered for the opportunity to sing hymns "shape-note" style, a type of music in which notes are designated by geometric shapes that has been a folk tradition for hundreds of years.

"I find the songs very thrilling to hear and sing," said Smith, who joined the group two years ago.

Like many of those who regularly gather to sing shape-note music, Smith heard about the group through the local Folklore Society; she went to her first Sunday meeting to get away from the Super Bowl.

"I would say that, really, we are a secular group who gets together to sing Christian hymns," she said.

Fritz von Fleckenstein said he likes the music because "it's an older kind of harmony."

"I like early music, and there is something quite satisfying about shape-note," he commented.

Shape-note music provides a unique, old-fashioned harmony, members of the group explained. The style generally is characterized by the tenor carrying the melody. The soprano is the treble in shape-note singing. Also, men can sing the top line, and women can sing the third line of music, unlike standard musical interpretation in which women sing the top two lines and men the bottom.

"This makes for a richer harmony," Smith said.

Instead of having the eight traditional notes, shape-note music has four geometric patterns for notes. A diamond signifies the musical note "mi," a triangle "fa," a circle "so," and a square "la." The pattern is repeated up the scale.

Smith said that she remembers which notes the shapes stand for this way: "La is a square (as in 2 Ls together), and mi is a diamond (as in 'diamonds are for me')."

The group sings from the Original Sacred Harp songbook, a compilation of shape-note hymns that was first published in 1844. The notes are printed on a scale that is similar to traditional music so that people who do not know the codes can follow the tune.

On the fourth Sunday of every month, members meet in homes all over the Washington area. Many of those involved participate in other singing activities such as church choirs and madrigal groups. Newcomer Corrie Ernst sings with an opera company, and Ruth and Fritz von Fleckenstein sing Gregorian chants at a Latin mass.

After gathering in a circle, someone calls out a hymn for the group to sing, a note sounds from a pitch pipe, and the room begins to ring with the sound of voices in harmony.

"There are some funny, quaint lyrics that you come across; there is one line about 'vegetation flying,' " said Smith, "and you get an image of broccoli whizzing by."

Mary Helen Shortridge, who started the group with her husband more than 20 years ago, said: "Some of the songs are so strange and exciting because of the harmony. The music is really interesting to sing.

"You are hearing music that people were singing 150 years ago, and the gloominess of life and death is right there in it," she continued. "If we don't sing these songs they are going to die, and they are so beautiful we don't want them to."

While the original gatherings of shape-note singers served to perpetuate the spiritual message of the hymns, much of the appeal of today's gatherings seems to be in the spirit of comfortable informality.

There are laughs when the high notes are missed, and one singer noted that a certain refrain "sounded like Gilbert and Sullivan in shape-note."

The group sings for two hours, breaks for dinner, and then resumes singing for two hours. Traditionally, the last song before the break is "Northfield," a 1701 hymn by Isaac Watts that asks: "How long, dear Savior, O how long shall this bright hour delay?"

Then, in a rousing burst of harmony, the chorus changes to "O how long shall the dinner hour delay, dinner hour delay?"